Calls to reassert Congressional authority over US war-making failed to muster enough votes to override President Trump's veto of the Yemen War Powers resolution, which demanded Trump withdraw US involvement from the unauthorized war. The vote was 53-45, short of the two-thirds majority needed to override. 

Opposition to the war was driven by the war crimes being committed by the US-backed Saudis, and the Saudi assassination of Jamal Khashoggi, which had some in Congress questioning the US backing them in a war. 

The Trump Administration argued variously that Yemen didn't count as a war, that Trump had unilateral authority on the war, and that the war in Yemen would be bad for Iran and therefore in America's interests.

Though none of these arguments stood up to close scrutiny, the Republican leadership in the Senate broadly echoed them. Ultimately, this was still enough to keep the veto from being overridden.