Charles Krauthammer believes President Trump will likely be vague on the expected repeal-and-replace of ObamaCare when he addresses a joint session of Congress on Tuesday.

"I guarantee you he will not be specific at all," Krauthammer said on "Special Report," adding that the specifics of his plan have yet to be ironed out and specificity is "not what you want to do" in a speech like that.

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"This is essentially a State of the Union Address," he explained.

Krauthammer said he expects that Trump will chiefly restate the Republican Party's principles during his speech, and he will avoid spending extended time on ObamaCare.

He noted that during a speech to a group of governors on Monday, Trump expressed his disbelief at the complexity of the health care law.

Kruathammer said that the president finally understands that this is the "most complex issue in American politics," and it has been since then-First Lady Hillary Clinton drafted "HillaryCare" in the 1990s.

He added that ObamaCare is "internally collapsing," and that makes the problem even harder for Trump to address.

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