Sen. Cory Booker and Oona Hathaway call out Trump for planning to keep U.S. troops in Syria indefinitely:

But the president doesn’t have the power to unilaterally make the decision to commit American troops to stop Mr. Assad by force. He needs to make his case to Congress and the American people, as well as the international community. Inserting American troops into this situation on his own is not just bad policy, it is illegal under both the Constitution and international law.

It is encouraging to see some more opposition to Trump’s illegal war in Syria. Booker and Hathaway are correct that what Trump proposes to do (and what he’s already doing) in Syria breaks the law. The 2001 AUMF has been distorted and abused to cover a multitude of unnecessary wars over the last sixteen years, but there is no way that the administration can hide behind it this time.

Booker and Hathaway’s op-ed would have been much stronger if they had emphasized that the U.S. military presence in Syria has been illegal from the start. Whatever one wants to say about the war on ISIS inside Iraq, the U.S. had no right to expand it into Syria. The U.S. had no right to put troops inside Syria without the permission of their government, and it still doesn’t. The U.S. has been trampling on international law in Syria for over three years. The difference now is that Trump is proposing to continue doing so without having the fig leaf of counter-terrorism to cover it up.

The authors’ conclusion is correct:

For several decades now, Congress has gradually ceded its war authority to the executive branch. If it does not act now, it may lose what authority remains. Congress has to attend to its constitutional duties: Our troops and their families deserve a public debate over the precise scope of their mission if we’re asking them to put their lives on the line. Congress must tell the president he cannot engage our troops in an illegal war in Syria. To allow this blatantly illegal action would spell the end of congressional authority over war.

The danger in allowing Trump’s illegal war in Syria to go ahead uncontested is not just that it will let an incompetent president commit the U.S. to an open-ended mission in a devastated and war-torn country without authorization or debate, but that it will mean the president can ensnare the U.S. in wars of his choosing without any involvement from Congress. You may not care about what Trump is doing in Syria today, but you will care about what he or some other president chooses to do with this usurped authority elsewhere.