President Trump responded to harsh criticism from Sen. Lindsey Graham (R-S.C.) over the events unfolding in northern Syria, saying that Graham should focus on his work chairing the Senate Judiciary Committee, and accusing Graham of obsessing over war in the Middle East.

"Lindsey Graham would like to stay in the Middle East for the next 1,000 years with thousands of soldiers fighting other people's wars. I wanna get out of the Middle East. I think Lindsey should focus right now on Judiciary, like the Democrats — the do-nothing Democrats as I call them because they're doing nothing, they're getting nothing done. They're not getting USMCA done between Canada, the United States and Mexico. They're getting nothing done."

— President Trump

The other side: Graham, usually a loyal Trump ally, reprised his condemnation of the president's decision to withdraw troops from northern Syria on Wednesday, expressing disbelief at comments he made earlier about U.S.-allied Kurdish forces not being "angels."

Graham tweeted that if Trump "continues to make such statements this will be a disaster worse than President Obama's decision to leave Iraq."

"If the President did say that Turkey's invasion is no concern to us I find that to be an outstanding — an astonishing statement which I completely and totally reject. ... If you're not concerned about Turkey going into Syria why did you sanction Turkey?"

He said later: "I will do anything I can to help him, but I will also become President Trump's worst nightmare. I will not sit along the sidelines and watch a good ally, the Kurds, be slaughtered by Turkey... This is a defining moment for President Trump. He needs to up his game."

Worth noting: Trump's comments about Graham's desire to keep thousands of troops in the Middle East come days after he authorized sending 3,000 more U.S. troops to Saudi Arabia in order to combat the threat from Iran.

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