Hyper-partisanship. Excessive debt. Foreign influence in our elections. Sounds like a litany of some of America’s greatest challenges.

But some threats never end and these topped the list of what kept George Washington up at night, fearing for the future of the nation he helped found.

They were cautionary touchstones of Washington’s final revolutionary act: a Farewell Address in which the nation’s first president voluntarily stepped down from power, establishing the two-term tradition. Instead of delivering the message to Congress, Washington instead delivered it directly to the American people in the pages of a Philadelphia newspaper on September 19, 1796. It quickly became the most famous address in the nation, more widely reprinted than the Declaration of Independence for the first 100 years of our republic.

No valedictory victory lap, Washington’s farewell warning was a prescient document, full of durable wisdom that inspired and informed presidents from Lincoln to Eisenhower to Reagan and Obama, to name just a few. Below, are examples of how great statesmen have studied and applied the lessons of history, providing a conversation across the ages:

Civil War was the revolutionary generation’s greatest fear, preoccupying George Washington’s presidency. But two generations later, war loomed. And during the 1860 presidential campaign, the nominee of the newly formed Republican Party, Abraham Lincoln, cited the Farewell Address repeatedly in his stump speech, calling out the divisiveness that had led the nation to the brink:

“Some of you delight to flaunt in our faces the warning against sectional parties given by Washington in his Farewell Address,” Lincoln said. “Could Washington himself speak, would he cast the blame of that sectionalism upon us, who sustain his policy, or upon you who repudiate it? We respect that warning of Washington, and we commend it to you, together with his example pointing to the right application of it.”

In the heat of the presidential campaign, Lincoln presented himself as Washington’s heir, defending his legacy against the secession-threatening southern Democrats. Lincoln nailed the hypocrisy of men who tried to twist history to their advantage while ignoring original intentions, “calling not the sinners, but the righteous to repentance…imploring men to undo what Washington did.”

One month after Lincoln was inaugurated, the southern states launched the Civil War by firing on Fort Sumter in South Carolina. Washington’s worst fear had come to pass.

But the Farewell Address remained a means of rallying what was left of the Union. With the war raging, citizens of Philadelphia, to commemorate Washington’s first birthday celebration since the rebellion’s outbreak, petitioned Congress to read “that immortal Farewell Address which even in the pages of British history is pronounced ‘unequaled by any composition of uninspired wisdom.’ ”

In response, Lincoln issued a presidential directive that Washington’s birthday be commemorated in 1862 with readings of the Farewell Address nationwide, including “at every military post and at the head of the several regiments and corps of the Army.”

The extensive excerpts selected by Lincoln focused, logically enough, on the need to maintain a strong national union. Washington’s words took on renewed urgency against the backdrop of civil war:

“The unity of government which constitutes you one people is also now dear to you. It is justly so, for it is a main pillar in the edifice of your real independence, the support of your tranquility at home, your peace abroad; of your safety; of your prosperity; of that very liberty which you so highly prize…it is of infinite moment that you should properly estimate the immense value of your national union to your collective and individual happiness; that you should cherish a cordial, habitual, and immovable attachment to it; accustoming yourselves to think and speak of it as of the palladium of your political safety and prosperity; watching for its preservation with jealous anxiety; discountenancing whatever may suggest even a suspicion that it can in any event be abandoned; and indignantly frowning upon the first dawning of every attempt to alienate any portion of our country from the rest.”

Government unity was now existentially threatened—in fact rather than theory. Now its fate would be determined on battlefields, as soldiers confronted the ultimate attempt to “alienate any portion of our country from the rest.” While Union soldiers gathered to listen to the Farewell read by their commanders in the field, a grand procession was occurring beneath the U.S. Capitol dome, which was still under construction. Lincoln ordered members of the House and Senate, as well as cabinet officials and justices of the Supreme Court, to witness a reading of the Farewell Address on Saturday, February 22, at noon.

It remains a Senate custom that continues to this day.

The second-most-famous farewell address in presidential history was Dwight D. Eisenhower’s wise warning against the rise of the military-industrial complex.

In May 1959, he pulled aside his chief speechwriter, Malcolm Moos, and said, “I want to say something when I leave here.” He envisioned a 10-minute farewell address to the American people. Moos recalled, “I think the statement was prompted by a book…that Alexander Hamilton drafted Washington’s Farewell Address.”

This spark of insight was relit by White House speechwriter Frederic Fox in a memo to Moos, dated April 5, 1960:

As the time for the president’s retirement draws near, I recommend your re-reading the “Farewell Address” of George Washington. It is a beautifully wise and modest piece by a faithful public servant who loved his country.”

He went on to say: “I was struck by its relevance to our day: the call for Constitutional obedience; the warnings about sectionalism; the dangers of ‘overgrown military establishments’ but the necessity of maintaining a ‘respectable defensive posture;’ the realistic attitude towards ‘that love of power and proneness to abuse it which predominate in the human heart;’ the unhappy tendency of mankind ‘to seek security and repose in the absolute power of an individual;’ the necessity for an enlightened public opinion; the ungenerous habit of one generation to spend beyond its means and to throw ‘upon posterity the burden which we ourselves ought to bear;’ the broad diplomatic advice. And much more.”

Eisenhower’s farewell address offered a defiant coda to his own presidency, with numerous parallels to the founding father, from highlighting his own instinctive political independence and disdain for partisan politics to speaking to the American people directly, rather than through the filter of an address to Congress. But what he most borrowed from Washington was the frame of the farewell as a warning to future generations.

Eisenhower wanted to caution his fellow Americans about the growing strength of what he first called “the military-industrial-congressional complex,” defining a new trend in American government. But the outgoing president identified the emerging issues of our era long before the advent of the internet or the time when the number of Washington lobbyists would outnumber members of Congress.

“We must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military-industrial complex,” Ike said from the Oval Office on the night of January 17, his gray suit flickering on the black-and-white TV sets of the time. “The potential for the disastrous rise of misplaced power exists and will persist. We must never let the weight of this combination endanger our liberties or democratic processes.”

Eisenhower’s farewell address especially echoed Washington’s one-time warning against “those overgrown military establishments which, under any form of government, are inauspicious to liberty, and which are to be regarded as particularly hostile to republican liberty.”

The fact that two of our most famous generals-turned-presidents took time to warn about the military establishment’s instinct to increase its power is a sobering commentary on the culture they knew so well. They were in unique positions to offer an honest critique: No serious politician could credibly accuse Washington or Eisenhower of being weak on national defense.

Ultimately, the overarching prescription from President Eisenhower was similar to what Washington had counseled as the ultimate check and balance: vigorous citizenship.

“Only an alert and knowledgeable citizenry,” Ike advised, “can compel the proper meshing of the huge industrial and military machinery of defense with our peaceful methods and goals, so that security and liberty may prosper together.”

Ike’s advancement of the Farewell Address gave it renewed relevance in an atomic age.

Eisenhower also sounded the clarion call for generational fiscal responsibility: “As we peer into society’s future, we—you and I, and our government—must avoid the impulse to live only for today, plundering for, for our own ease and convenience, the precious resources of tomorrow. We cannot mortgage the material assets of our grandchildren without asking the loss also of their political and spiritual heritage. We want democracy to survive for all generations to come.”

More than a century and a half later, Washington’s Farewell Address was still inspiring successors to follow its precedent—a presidential warning to future generations about the forces poised to derail our democratic republic.

Ronald Reagan found inspiration in Washington’s Farewell from a specific section: the importance of morality and virtue to a self-governing people, most often secured through religion.

Reagan quoted the Farewell Address on religion frequently, often when arguing for a constitutional amendment to allow prayer in schools. But Reagan’s most eloquent invocation of the Farewell came during his speech at Moscow State University in 1988.

It was a moment loaded with high drama: the conservative Cold Warrior speaking to students in the heart of the Soviet Union about his hopes for lasting peace amid the reforms of perestroika and a thawing Cold War—even as America and Russia kept nuclear weapons trained on each other’s cities.

“Freedom, it has been said, makes people selfish and materialistic, but Americans are one of the most religious peoples on earth,” Reagan said.

“Because they know that liberty, just as life itself, is not earned, but a gift from God, they seek to share that gift with the world. ‘Reason and experience,’ said George Washington in his Farewell Address, ‘both forbid us to expect that national morality can prevail in exclusion of religious principle. And it is substantially true, that virtue or morality is a necessary spring of popular government.’ ”

“Democracy is less a system of government than it is a system to keep government limited, un-intrusive,” he continued, “a system of constraints on power to keep politics and government secondary to the important things in life, the true sources of value found only in family and faith.”

For Republicans spreading the gospel of freedom to an officially atheist state, Washington’s counsel about the role of faith and morality in a democracy took on new relevance.

On January 10th, 2017, President Barack Obama carried forward the tradition begun by Washington’s Farewell, warning his fellow citizens about threats to our democracy. In front of an adoring crowd of thousands that packed Chicago’s McCormick Place convention center, Obama connected with Washington’s wisdom directly by quoting the first Farewell Address at length, giving it new prominence for a new generation:

“In his own farewell address, George Washington wrote that self-government is the underpinning of our safety, prosperity, and liberty, but ‘from different causes and from different quarters much pains will be taken…to weaken in your minds the conviction of this truth’; that we should preserve it with ‘jealous anxiety’; that we should reject ‘the first dawning of every attempt to alienate any portion of our country from the rest or to enfeeble the sacred ties’ that make us one.”

Obama explained the continued relevance of the quote from Washington’s Farewell, saying: “We weaken those ties when we allow our political dialogue to become so corrosive that people of good character are turned off from public service; so coarse with rancor that Americans with whom we disagree are not just misguided, but somehow malevolent. We weaken those ties when we define some of us as more American than others…

It falls to each of us to be those anxious, jealous guardians of our democracy; to embrace the joyous task we’ve been given to continually try to improve this great nation of ours. Because for all our outward differences, we all share the same proud title: Citizen.”

Over multiple drafts of the speech President Obama wrote with his chief speechwriter Cody Keenan, the core quote from Washington’s Farewell remained intact:

“It was in his consciousness, especially given the Washington Farewell’s focus about warning against hyper partisanship and the importance of national unity,” Keenan later explained to me, explaining the president’s reverence for the office confronting his concern about candidate Trump’s record of trolling in Birtherism and tearing down democratic norms and institutions. “The reason we used that Washington line was because a lot of times we all fall prey to this: We just accept people trying to divide us and tear us apart and convince us that one aspect of American society is inevitably corrupt or not to be trusted. And it is entirely up to us to believe that or not.”

Across the span of two and a half centuries, our country’s slave-owning first president and his African-American successor found considerable common ground and continuity of purpose.

Confronting the dangers of division to democracy, both Washington and Obama understood the same transcendent truth: Our independence as a nation is inseparable from our interdependence as a people.

Washington’s Farewell Address echoes on across the ages, perhaps now more relevant than ever before.

John Avlon is a journalist and political commentator. He is the author of such books as Independent Nation: How Centrists Can Change American Politics, Wingnuts: How the Lunatic Fringe is Hijacking America, and Washington’s Farewell: The Founding Father’s Warning to Future Generations. Follow him on Twitter at @JohnAvlon.

History Reads features the work of prominent authors and historians.