Is there any logical reason for Trump to.. do this? I don't get it
Trump is ideologically opposed to American resources and soldiers being used over seas in conflicts that he thinks should be dealt with by someone else. Trump had already ceded some of the front with ISIS and terrorists in Syria to be fought by Assad's army, Iran, and Russia, back in ~2017. This would be a similar move with Turkey.
Wait, how can they reverse or mitigate his decision? And even if they could, why would they do it if it will put them in Trump's crosshairs politically?
Trump has shown a willingness to backdown on abrupt, incoherent foreign policy decisions when a quorum of Republicans, and notably Fox news commentators, don't back those decisions.
Particularly his original Tweet announcing a withdrawal from Syria, or more recently when he said hed be completely closing the Mexican border in ~24 hours.
I think these Republicans are going public because they know getting Fox News to support (or report on) their decision will be the best way to influence Trump, where going privately to him won't work as well because he just supports whatever foreign policy decision that the last person who talks to him supports.