>the resulting carnage will cost him his remaining support among Republicans at all levels *including the MAGA faithful*
Doubt
Doubt
And even of those who are in love with Trump's image, this may tarnish the image enough for some of them to fall out of love with it.
It won't cost him all of MAGA. But it will cost him some.
MAGA obviously doesn't care about carnage that we dole out to the Iranians, including Iranian children, but they presumably will object to a tide of body bags arising from the actions of a President who promised them "No more foreign wars."