Going to war in "the Middle East is the worst decision ever made in the history of our country!" President Trump tweeted last week. "Now we are slowly & carefully bringing our great soldiers & military home."

But are we? Just two days later, the Pentagon announced 1,800 additional U.S. troops will be deployed to "assure and enhance the defense of Saudi Arabia," which, "with other deployments ... constitutes an additional 3,000 forces that have been extended or authorized within the last month." That's a major new commitment to Riyadh's security, and it brings the total new deployments in the region since May to 14,000. Meanwhile, even more American forces, including warships currently sailing the Pacific, may move to protect Saudi Arabia soon.

The discrepancy between Trump's statements and his policies is conspicuous. While he regularly speaks of ending endless wars, the president so far has done little to meaningfully apply his critique to U.S. foreign policy. But that inconsistency isn't the only problem here: Sending these troops to Saudi Arabia also sets up a new version of the dilemma we just faced with the Kurds in Syria. In each case, deployment comes with a strong suggestion that we'd fight for the partner in question. Would we really fight for Saudi Arabia?

The United States' 18-year entanglement in the Middle East is demonstrably a costly and dangerous debacle. Nation building is no task for the American military and largely has been an exercise in futility. U.S. troop totals in the Middle East should be decreasing, not increasing.

Trump has said all of this, but none of these insights are reflected in his strategy. Instead, his administration is further entrenching U.S. involvement in Saudi Arabia's regional and religious rivalry with Iran. The goal of this new deployment is to "send the message to the Iranians, do not strike another sovereign state, do not threaten American forces," said Joint Chiefs Chair Gen. Mark Milley. Esper likewise characterized the move as a "response to Iranian provocations."

So as tensions between Riyadh and Tehran escalate, Washington is telegraphing its willingness to fight for the House of Saud — even more explicitly than it indicated a willingness to fight for our Kurdish partners in Syria.

That's how this deployment repeats the mistake of overcommitting U.S. support for non-treaty partners that we've seen play out with disastrous results for the Kurds this month. And the same disappointment may well follow, as the Trump administration is setting up a perverse incentive for Saudi Arabia and Iran as well as a future predicament for the United States.

Here's how we get there: Current assurances of American support encourage Riyadh to be aggressive in its dealings with Tehran, rejecting options to de-escalate and seek a peaceful, diplomatic resolution (or at least a stalemate or balance of power both can accept). With the most powerful military in the world at its side, Saudi Arabia may well be emboldened to ratchet up hostilities toward Iran — while Iran, feeling threatened by its enemy's position of strength, will become even more provocative in an attempt to prove itself a formidable adversary. For both sides, U.S. intervention fosters behavior that makes war more likely.

If mutual escalation continues, however, Washington eventually will have to choose: Do we follow through on the pledge to fight for Saudi Arabia, becoming embroiled in a major new conflict? Or do we disentangle from the region's squabbles, declining to wage war at Saudi behest after years of suggesting we would do exactly that? Neither option is good, but both can be avoided by changing course now.

Saudi Arabia is unworthy of unconditional U.S. support. Like the Kurds, it is not a treaty ally of the United States — nor should it be, as its government is a brutal dictatorship well known to contribute to regional chaos, most visibly at present through its U.S.-enabled war in Yemen. Unlike the Kurds, it is a wealthy state perfectly capable of handling its own defense. Rather than deploying more American forces to protect an oppressive regime that has no obligation to do the same for us, Trump should finally make good on his many promises to bring U.S. soldiers home.

This is a straightforward and realistic way to reject recreating the dilemma we had in Syria, and it avoids plunging us into rising conflict between Saudi Arabia and Iran, a religious clash our government little understands and should not try to manipulate. Trump's tweeted takedowns of these past two decades of war get a lot right. But just talking about ending endless wars isn't enough, and sending thousands of Americans for fight for Saudi tyrants does not bring us closer to peace.

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