Protesters demonstrate at the UN offices in Sanaa in November 2017.Khaled Abdullah / Reuters

The Senate faced down Donald Trump on Thursday, demanding the withdrawal of U.S. support for the Saudi-led war in Yemen by a resounding bipartisan margin, then unanimously declaring the Saudi crown prince responsible for the murder of the journalist Jamal Khashoggi. It was a historic challenge not only to the president, but also to the nature of the U.S.-Saudi relationship, which has spanned some seven decades.

Except that it won’t actually get the U.S. out of the war. So what was the point?

In short, it was more about politics than policy—and the political shift has been rapid and significant ever since Khashoggi’s death in October. Suddenly, even traditional stalwarts of the Saudi alliance in the Senate, such as the South Carolina Republican Lindsey Graham, were lining up to condemn what they called the Kingdom’s recklessness, demanding a change in its behavior. Lawmakers who declined to even debate the same Yemen measure earlier this year were now castigating the Saudi leadership from the Senate floor, citing Khashoggi and Yemen in the same speeches as symptoms of a young Saudi leader out of control.

And in the face of an administration that has repeatedly defended Saudi Arabia’s de facto ruler, Crown Prince Mohammed bin Salman, from allegations that he was responsible for Khashoggi’s death, it was a rare moment of a Republican-held Senate trying to flex authority over two of the most important aspects of U.S. foreign policy: the nature of alliances and the decision to wage war. As Democratic Senator Chris Murphy, a co-sponsor of the resolution, vowed at a press conference on Wednesday: “If this administration doesn’t reorient our policy toward Saudi Arabia, then Congress is going to do it.”

The Senate can’t do it alone, however. The measure would still have to pass the House, which has said it won’t vote on it this year, and be signed by the president—who has stuck by MbS, as the crown prince is known, but also signaled openness to withdrawing from Yemen—to become law. Even some critics of the Saudi-led war in Yemen, such as Graham, argued that the resolution, which relies on a controversial law saying Congress can stop U.S. forces’ participation in hostilities they haven’t authorized, wasn’t the appropriate tool—and in any case, that U.S. support for the Saudis in Yemen didn’t count as active hostilities.

What all this adds up to is a set of major foreign-policy questions that will grow only more urgent next month, when a new, Democratic-led House convenes, with the Senate having vowed to keep up the pressure on Saudi Arabia. Those concerns go far beyond the immediate debate over how much more the United States should punish the Saudi regime for Khashoggi’s death, given that the Trump administration has already sanctioned 17 Saudis for their alleged roles.

More broadly, there is growing congressional unease with aspects of the U.S.-Saudi partnership, which Trump has made the pillar of his entire Middle East strategy, particularly with regard to confronting Iran. It’s this aspect of the relationship especially that administration officials have warned is at risk in the outcry over Khashoggi’s killing, arguing that the fate of one man shouldn’t be allowed to damage a productive partnership against a mutual adversary.

Congressional worries have only grown since February, when two Democrats and one Republican first introduced the just-passed resolution, which initially went nowhere. Even then some members were clearly disturbed by U.S. support for the Saudi-led campaign in Yemen, which began under Barack Obama’s administration in 2015. After Houthi rebels, who are aligned with Iran, overthrew the internationally recognized government in Sanaa, Saudi Arabia intervened against them to restore the government, with the U.S. providing limited support. That help took the form of refueling aircraft and of some intelligence assistance, in part to help Saudis limit civilian casualties. It was also an effort to prove to the Saudis that Washington would aid an important ally to contain the spread of Iranian influence.

It didn’t turn out that way. The reports kept coming—of weddings bombed, of school buses, of funerals. Widespread starvation broke out, then cholera. Iran’s influence seemed only to grow as it funneled more weapons to the Houthis. By the spring of 2018, the Republican chair of the Senate Foreign Relations Committee, Senator Bob Corker, was citing the 22 million people in need of humanitarian assistance in Yemen and had convened a hearing to examine the way forward—and how the United States should be involved. By summer, the ranking Democrat on the committee, Senator Bob Menendez, was threatening to hold up arms sales to the Kingdom. He described then his concern that “our policies are enabling perpetuation of a conflict that has resulted in the world’s worst humanitarian crisis.”

That was before Khashoggi disappeared from a Saudi consulate in Istanbul; before it became clear that he’d been murdered; before the Saudi government admitted to official involvement even as it denied MbS’s culpability; and before the CIA reportedly concluded that the crown prince, a White House favorite, had most likely ordered the hit.

The war, the journalist, and evidence of an ongoing crackdown on dissidents in the Kingdom galvanized a broader suspicion about the crown prince’s behavior, notwithstanding his widely celebrated moves to modernize the country. (The Saudis deny that such a crackdown is taking place.) The administration ended refueling support to the Saudi air campaign and accelerated efforts to seek a negotiated end to the Yemen conflict through the United Nations. But the Senate pushed for more. By December, the Senate voted overwhelmingly to advance debate on the resolution that had failed to find its way to the floor just months before, setting up this week’s showdown in the Senate.

The Senate furor contrasts with the defenses of the crown prince from not only the White House but the State Department and the Pentagon. Secretary of State Mike Pompeo and Defense Secretary Jim Mattis personally briefed senators on the Khashoggi killing and cast doubt on the CIA’s reported assessment about the crown prince’s involvement. When it came to the Yemen war, officials argued that withdrawing U.S. support would only endanger more lives by depriving the Saudis of American help with precision targeting, and praised the Saudis for providing humanitarian funding. Even as the Senate was debating this week, the Yemeni government and the Houthis were holding their first direct peace talks in Sweden.

The measure would have won still more supporters, but some legislators, such as Graham and Senator Marco Rubio, voted against it. Despite voicing anger over Saudi Arabia’s actions in Yemen and over Khashoggi’s killing, they opposed this particular resolution, with some, like Corker, championing alternative legislation and others, like Rubio, arguing that completely withdrawing support for the Yemen campaign would be counterproductive.

Others saw an opportunity to advance objectives unrelated to Khashoggi. There was the long-standing bipartisan concern that whatever the U.S. was doing to help the Saudis limit civilian casualties in Yemen was not only not working, but making the U.S. complicit in the world’s worst humanitarian catastrophe.

There was also the question of Congress’s power to decide when and where the United States was at war. Again, the concern was bipartisan, with Republican Senator Mike Lee and Democratic Senator Tim Kaine raising questions about whether the president could legally involve the U.S. in sustained hostilities without congressional approval.

It’s unclear why this conflict is where senators have decided to debate war powers, given that they have declined to do so in the cases of much more direct U.S. interventions, notably in Syria. But the debate may also presage a more assertive Congress—with Democrats in control of the House starting in January—poised to exercise more scrutiny over U.S. participation in a variety of conflicts all over the world.

What it is unlikely to do in the short term, however, is fundamentally alter the U.S.-Saudi relationship, even if it marks a step in a slow decline. The relationship has survived other crises, including the revelation that 15 of the 19 September 11 hijackers were Saudi. There is still no substitute for the U.S. partnership to help guarantee Saudi security. For their part, the Saudis are likely to swallow this bitter pill from Congress, assured for the moment of White House support.

Yet the fact that the war in Yemen is the subject of vigorous debate after so many years means something significant has changed in American politics. When that happens, sooner or later, American policy tends to catch up.

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