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The people who are supposed to be President Trump’s biggest political allies are not happy with him.

These people — congressional Republicans and even members of Trump’s own administration — are unhappy with his foreign policy. They’re also unhappy with how he is handling year-end budget negotiations. And their dissatisfaction is a problem for Trump. It has already made him a weak president and could soon make him weaker.

The big news yesterday, of course, was the resignation of Jim Mattis, the defense secretary, who released a goodbye letter that contained an unusually detailed description of his disagreements with the president he had served.