Reuters ran a story that got a lot of attention last week. The headline: "Exclusive: Trump says Republican border tax could boost U.S. jobs." Republicans who support border adjustment immediately celebrated — blasting out press releases trumpeting Trump's comments.

Here's what Trump actually said to Reuters: "I certainly support a form of tax on the border ... What is going to happen is companies are going to come back here, they're going to build their factories and they're going to create a lot of jobs and there's no tax."

The problem: In the days following Trump's comments, we've heard that his top economic advisor Gary Cohn is less than enthusiastic about the tax, and yesterday on Fox Treasury Secretary Steve Mnuchin expressed deep reservations about the tax. Even public supporters of the proposal — the same folks who have to publicly say that Trump is on board — admit privately they have no idea what's in his head.

Between the lines: A source who's worked closely with Trump tells us that when Trump hears border adjustment tax, he's often hearing "border tax." That could be something very different. Remember that the only idea in this realm that Trump has spoken of publicly and enthusiastically is his idea to punish American companies that move factories overseas with 35 percent import tariffs when they try to sell their goods back into the United States. That's very different than a tax levied on all imports.