Story highlights McCain has sharp critiques of the President

McCain hasn't personally thwarted any elements of Trump's agenda, yet

Washington (CNN) Now that he has returned to the Senate for another six years, Sen. John McCain is back to being a president's biggest headache on Capitol Hill.

The Arizona Republican bashed President Donald Trump's White House as an "administration in disarray" while attending a security conference in Munich. Then, on NBC's "Meet the Press," he blasted Trump's attacks on the media, saying "the first thing that dictators do is shut down the press."

The sharp critiques of the President come as McCain sheds his campaign-trail reluctance to criticize Trump -- or even say the then-Republican nominee's name.

McCain, who was the party's nominee himself in 2008, has long been comfortable on the bad side of presidents. The Armed Services Committee chairman trashed George W. Bush's tenure over his handling of the Gulf War and the mounting national debt and constantly accused President Barack Obama of weak leadership abroad.

"I'm the one that said Ronald Reagan shouldn't send Marines to Afghanistan," McCain told CNN in early February. "I'm the one that said Donald Rumsfeld should be fired. I've said the general in Afghanistan should be fired. Look, I have done what I have done right for this country under Republican and Democrat presidents. I will continue to do so. This is not a departure from the way I've conducted myself in the United States Senate."

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