Editor’s Note: S.E. Cupp is the author of “Losing Our Religion: The Liberal Media’s Attack on Christianity,” co-author of “Why You’re Wrong About the Right” and a columnist at the New York Daily News. The opinions expressed in this commentary are hers.

Story highlights

President Obama objects to comments by two senators from his own party: Elizabeth Warren, Sherrod Brown

S.E. Cupp: The president should let these kinds of comments rest without responding in personal terms

CNN  — 

Well into his second term in office, you’d think the President would have toughened up a bit.

But when it comes to tests of party loyalty, President Obama’s skin is still surprisingly thin.

S.E. Cupp

We saw that this week, not once but twice within the span of a single debate on his Trans-Pacific Partnership trade deal, which was stymied by Senate Democrats.

First, Obama struck back at his friend Sen. Elizabeth Warren for her criticism of the trade deal, calling her “absolutely wrong.”

“Her arguments don’t stand the test of fact and scrutiny,” he said. And the zinger: “Elizabeth is, you know, a politician like everybody else.”

A more diplomatic, less defensive version of that might have sounded like this: “The senator is entitled to her opinion and I appreciate her passion, but we just happen to disagree.”

But the hurt feelings continued. Unbelievably, the White House has asked for an apology from Sen. Sherrod Brown, who, while defending Warren’s criticism, accused the President of making a legislative battle too personal.

Brown also seems to have struck a nerve when he suggested that Obama was “disrespectful” to Warren when he called her by her first name. The Democrat from Ohio said of the President, “… he might not have done that for a male senator, perhaps?”

Now, that latter assertion is downright loopy. Obama and Warren are friends, and he calls plenty of men by their first names, too. But it’s so silly, in fact, that the White House needn’t dignify it with a response. Asking for an apology is more the stuff of kindergarten teachers than of presidents with bruised egos.

The beauty of the third and fourth years of a second term is that by then a president has already weathered the tough stuff, and the hard-fought battles and petty bickering during tense election years are behind him.

You’ll usually see a more relaxed commander in chief who finally feels as though he can lighten up. He jokes more with the press corps. He’s playful with former rivals in Congress. He can laugh at himself.

Heading into 2016, the last thing Obama should want is to start trading barbs with members of his own party. My advice? Lighten up, Mr. President.

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