It's pathetic that some Republicans excuse is that the POTUS is a troll who throws out jokes.

Let's just call it like it is, they are supporting their side doing it. Republican hypocrisy is just endless. But their really is no point in calling them out on it, because they don't care. All they care about is political wins, and not the matter in which they are achieved.
State Department orders EU ambassador cited in Ukraine texts not to appear for deposition with House investigators
Just an hour before he was to speak infront of house investigators the state department orders the EU ambassador not to speak.
" If destruction be our lot, we must ourselves be its author and finisher.." - Abraham Lincoln
“ The Constitution be never construed to authorize Congress to - prevent the people of the United States, who are peaceable citizens, from keeping their own arms..” - Samuel Adams
Looks like it is even worse Donald Trump makes a lot of money from Turkey there's a twin Trump tower already in Istanbul.
“I have a little conflict of interest ’cause I have a major, major building in Istanbul,” Trump boasted in response. “It’s a tremendously successful job. It’s called Trump Towers — two towers, instead of one, not the usual one; it’s two. And I’ve gotten to know Turkey very well. They’re amazing people, they’re incredible people. They have a strong leader.” Donald Trump - 2015

Yes, i suggest that Erdogan would attack anyway. Because they would not believe US to actually care for Kurds enough. Remember Afrin?
Using US troops as "tripwire" to defend Kurds - provoking Turks into creating pretext for US attack on another NATO member - would be idiotic. They would issue warning - like they did through that Trump phonecall - and then attack anyway.
The upside would be... Kurds loving US slightly more while Turks will look even more toward Russia and others for their security if bluff would work?
And potential downside if it didn't? Destruction of NATO presence in the region and actual war with one of the largest regional militaries - when US already has tensions with Iran and things happening in Iraq as well.
The ambassador is certainly responding as if, yes, they do. Throw in a subpoena, and I'm pretty sure it becomes "no, they don't".
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Incidentally, this line -- with limited modification -- would also apply to Trump thinking that he could pay the Palestinians to leave Israel.