One of the gazillion things that have been said of Donald John Trump is that the president of the United States “doesn’t know what he doesn’t know.”

He seems to be the Bubble Boy of American politics, insulated from the effects of the barbs and boulders tossed at him. Or so he thinks.

Now comes former U.S. House Speaker Newt Gingrich to offer a bit of specificity, which is that Trump doesn’t realize just how “isolated” he has become.

Critics of this blog will recall that I’ve dismissed Newt in the past as a know-nothing has-been, a philanderer who in the late 1990s made a big case against former President Clinton over his, um, philandering. 

On this one, though, Newt might be on to something. He said on Fox News: “On the Hill, he has far more people willing to sit to one side and not help him right now, and I think that he needs to recognize he’s taken a good first step with bringing in Gen. (John) Kelly (as chief of staff), but he needs to think about what has not worked.”

Trump’s term as president is in trouble. He has declared open warfare on fellow Republicans. Democrats detest him already, so they need zero push to resist every single thing he proposes. He cannot fill key deputy Cabinet posts, or senior White House staff jobs. The roster of federal judgeships remains largely vacant.

The president’s legislative agenda has high-centered. It has no traction. Tax reform is likely to get stalled. He won’t get the money he wants to build that wall along our southern border. Congressional leaders are going to increase the budgetary debt ceiling despite what the president says.

Trump once boasted that “I, alone” can fix what’s wrong.

No, Mr. President. You cannot. It is impossible.

He doesn’t know what he doesn’t know … which is dangerous not just for him, but for the country.