Those searching for Senate Majority Leader Mitch McConnell's (R-Ky.) big break with President Trump may have found it.

"In January, a supermajority of the U.S. Senate voted for an amendment that expressed bipartisan concern about the continuing threat posed by ISIS and Al Qaeda in Syria, appreciation of the long-term American security interests in Syria and the region, and support for a continued military presence in northeastern Syria," McConnell said in a statement Monday in reaction to Trump's decision to pull back American troops from the Syrian-Turkish border. "The conditions that produced that bipartisan vote still exist today."

Yes, everyone from Rep. Ilhan Omar (D-Minn.) to Pat Robertson, from CNN to Fox and Friends, denounced Trump's move. But against the backdrop of the Democrats' House impeachment inquiry, it is hard to read McConnell's comments as anything other than a warning to Trump. Senate Republicans are the firewall that prevent the president's removal. It would take 20 of them to vote to convict Trump to achieve that outcome.

McConnell might as well have said, "Nice Republican majority you've got behind you in the impeachment fight, Mr. President. It would be a shame if anything happened to it."

Indeed, with a few notable exceptions, like Kentucky's other senator, the Senate GOP very much remains George W. Bush's party on foreign policy. If the Democratic-controlled House votes to impeach Trump and he wants to remain in office, he can't afford to alienate many Republican members of the "supermajority" who are in favor of an indefinite military presence in Syria. Hawks like Sens. Marco Rubio (R-Fla.) and Lindsey Graham (R-S.C.) could become key votes — and they may cease to think their alliances with Trump are worth it if the troops start coming home.

Even without this Bush-Trump split on military adventurism and other issues, it's long been obvious that, as one top Republican staffer recently told The Atlantic's McKay Coppins, "If it was just a matter of magically snapping their fingers … pretty much every Republican senator would switch out [Vice President Mike] Pence for Trump." Syria helps move this preference from a matter of style to one of substance.

This might not sit well with the Republican base, which prefers Trump to what they see as the weak-willed GOP establishment so well represented in the Senate. That fact is undoubtedly Trump's strongest impeachment insurance. That's why it is no accident that Graham is comparing Trump, and the handful of mostly libertarian Republicans who support the president on this, to former President Barack Obama, who is rather less highly regarded by these same voters.

No doubt there are problems with the way Trump implemented his Syria move. Instead of creating conditions favorable to withdrawal, the people on the ground were surprised and dumbfounded. Trump's explanation was practically an invitation to Turkey to move against the same Kurds who were involved in the fight against ISIS. The president no longer has advisers around him who agree with him about endless wars — something for which only he is to blame. A poorly executed withdrawal could do more to delay a badly needed reset of our foreign policy.

>But even if he had executed the move better, it's hard to imagine that the bipartisan reaction would have been much different. We are told we are entering these wars to keep people living overseas from killing Americans. We then are told we must stay in these wars until further notice to keep people living overseas from killing each other. When Trump has escalated wars, he has largely heard applause. When he has even half-heartedly tried to wind one down, the nation's capital unites against him, and his own party protests the loudest.

For all the arguable abuses of power that have taken place under Trump, the unambiguous usurpation of Congress' power to declare war is seldom if ever seriously discussed as grounds for impeachment. It says a great deal about the state of affairs in Washington, D.C., that Trump may have marginally increased his odds of being removed from office by attempting to end a war Congress never authorized in the first place.

We've now redefined "wag the dog" to mean possibly ending such a war.

This is why our foreign policy never changes, despite what the voters may want. There are no legal and few political downsides to letting small wars continue forever on auto pilot. It's far riskier to pull the plug on them. Better for members to let the president assume all the risk, even if they think he is incompetent and the Constitution clearly says otherwise.

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