'The biggest mistake of his presidency': Lindsey Graham is hopping mad at Donald Trump — and the feeling is mutual

While many have long wondered whether President Donald Trump might have blackmail material that explains Sen. Lindsey Graham abrupt change from being a fierce critic to devoted defender of the man he once called a "race-baiting xenophobic bigot," another explanation has always been simpler and more plausible: The South Carolina Republican believes it's in his best interest to align with the White House.

That's true when it comes to getting re-elected in 2020 — Republicans who have split sharply with Trump have struggled to retain voters — and it's true when it comes to Graham's major focus in government: foreign policy. As long as he's on Trump's good side, Graham is better positioned to advocate for his hawkish view of American power.

This explanation of Graham's fealty to Trump is supported by his latest public feud with the president. Their break centers on a sharp disagreement over foreign policy. Graham, like most lawmakers, is outraged that Trump abandoned the United States' Kurdish allies in northern Syria, leaving them vulnerable to the ongoing onslaught from Turkey and creating upheaval in the region.

As the crisis has worsened, the split between Graham and Trump has widened.

At a Senate hearing on Wednesday, Graham declared Trump's withdrawal "the most screwed up decision I've seen since I have been in Congress."

In an interview on the 700 Club, Graham, clearly exacerbated, said: "Do you think [Turkish President] Erdogan would’ve done this if Reagan had been around?"

He told CNN that Trump "will have American blood on his hands if he abandons Kurds because ISIS will come back, and if any American is killed anywhere because a resurgent ISIS, it will fall on the Trump administration like it did Obama."

When asked about the criticism from Graham at a press conference on Wednesday, Trump clearly wasn't looking to be conciliatory.

"Lindsey Graham would like to stay in the Middle East for the next thousand years, with thousands of soldiers fighting other people's wars," Trump said. "I want to get out of the Middle East." (Despite this claim, Trump recently authorized sending thousands of more troops to Saudi Arabia, and the service members directed to leave northern Syria were not, in fact, brought home.)

"He's not listening to his advisers, he's not," Graham told CNN. "He's making the biggest mistake of his presidency by assuming the Kurds are better off today than they were yesterday. That is just unbelievable."

Infuriating key allies in the Senate and uniting them with Democrats seems like an unwise move with the body almost guaranteed to hold an impeachment trial in the coming months, but that's exactly what Trump has done — for no discernible strategic or substantive reason.

Asked by CNN whether he'd still support the president in 2020, Graham said: "I will tell you that I think his judgment here is flawed and people can make their own decision but Elizabeth Warren is no better. Bernie Sanders is no better."

He added: "At least he'll appoint better judges and he'll do other things."

Thus far, Graham has dismissed the calls to impeach Trump. But if he really grows concerned enough about the president's conduct, he may start to view removing the president as a better option. That way, in 2020, he wouldn't be forced to choose between Warren or Sanders and Trump — he could wholeheartedly endorse Mike Pence.