What will happen to President Obama's legacy now that President-elect Donald Trump is entering the White House?

Charles Krauthammer said on The Kelly File that "Obama's legacy is toast" and the president always knew what would happen if he was replaced by a Republican.

"It explains why he so desperately - and unusually in American history - campaigned so roughly against Donald Trump," he said.

Krauthammer said so many of Obama's achievements were "rammed" through Congress with little or no support from Republicans, including ObamaCare. He added that many other measures were executive orders or regulations "easily reversible" by a GOP successor. 

Krauthammer believes that Obama will end up as a "parenthesis" in American history because the country rejected the move to the left over the last eight years.

"He thought he was the Ronald Reagan of the left. ... Obama thought he would begin a liberal ascendancy the way that Reagan began a conservative ascendancy. Well, it did not turn out that way. The country rejected his policies," said Krauthammer.

Watch the full discussion above. 

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