Donald Trump ran for president promising to "Make American Great Again." But the result of his presidency is almost certain to be a massive, unprecedented decline in American economic strength and geopolitical status.

Can anyone doubt that his policies, combined with the president's insulting, mendacious, selectively obsequious words and behavior, will have the consequence of leaving the United States vastly weaker than it was before his election?

The U.S. has single-handedly started a global trade war that will sap our economic power — and we've done it with no clear aim beyond the amorphous goal of securing "better deals," with our clueless and feckless commander in chief in charge of the negotiations.

Trump has deliberately sabotaged the military alliance that has bound together the powers of the Western world for 70 years of unprecedented peace and prosperity and that has given the U.S. immeasurable leverage to further our national interests without having to resort to military force. His actions over the past 18 months are sure to set us on a path of vastly diminished influence around the world.

Trump has publicly prostrated America before Vladimir Putin, turning the U.S. into a global laughingstock that gladly welcomes meddling in our political system by hostile and flagrantly anti-liberal foreign powers.

Trump has shown America to be unreliable, with the bureaucracies of the executive branch often pursuing contradictory policies, and the president himself often undercutting them, turning us into global bunglers who constantly trip over ourselves, from Brussels and London to Jerusalem, Pyongyang, and Helsinki. The United States is now the geopolitical equivalent of a habitual drunk driver who repeatedly creates a hazard on the road, endangering himself and everyone around him.

How does any of this advance a coherent notion of American interests? What is the overarching strategy that would redeem, explain, or justify this behavior?

This isn't supposed to happen. Political leaders are supposed to act to advance their country's interests. Sure they can fail, making mistakes and misjudgments that lead to detrimental consequences. But they aren't supposed to act in ways that will obviously and deliberately damage the political community.

This, however, is exactly what President Trump is doing. His statements and policies clearly weaken and undermine America. They might not amount to national suicide, but they do point in the direction of intentional self-harm.

Trump's America-weakening words and deeds are not mistakes. George W. Bush's Iraq War was a mistake. Barack Obama's Libya intervention was a mistake. Both policies were undertaken with the intention of furthering American interests and the well-being of those who reside within the countries themselves. That turned out to be wrong, but the failure shows only that those who crafted and executed the policies made an error (or several of them).

One needn't assert that the status quo before Trump was perfect — or even good — or that it didn't stand to be revised or reformed in various ways to acknowledge that smashing that status quo along multiple dimensions simultaneously, with no indication at all that the person doing the smashing has engaged in even the most rudimentary thinking about precisely what he ultimately aims to accomplish, is astonishingly reckless.

Drastically reforming — nay, upending — American policy in even one area would be a major undertaking, requiring a considerable act of statesmanship. Upending them all at the same time without doing significant damage to the country would probably be impossible for anyone — let alone for someone as intellectually and temperamentally ill-suited to the presidency as Donald Trump.

To an observer watching from the outside, the United States during the Trump administration looks very much like an immensely wealthy and powerful country acting to take itself down a few pegs. As pundits have begun to realize, much of what the president is doing won't be reversible when he's gone. Point the nose of a passenger jet toward the ground at a sharp enough angle and at a certain point righting the plane becomes impossible — and the crash inevitable.

By elevating Donald Trump to the White House, the United States has opted in favor of its own decline. Historians of the future will need to answer the complicated question of how and why it happened. But that it happened won't be a matter of much dispute.