Approximately never. We are in a situation where Congress is unusually beholden to their constituents for once, because those people care deeply about Donald Trump. So this is what they want; not just the war, but everything -- they want all the power to rest with Trump.
> The war has record low approval ratings, even among Trump's base.
The war does, Trump does not. He maintains very strong support among the base, and that is the part keeping the GOP politicians in line. It is why some of them just resign instead of enduring the threats from his supporters.