After weeks and weeks of Trumpian attacks, and a full-scale revolt inside the Federal Reserve, Jay Powell finally opened the door to a rate cut, presumably in September.

The stock market promptly went up 900 points. And interest rates all along the Treasury yield curve went down.

So I guess we give Mr. Powell one cheer — out of three.

Noteworthy was Mr. Powell’s logic, which is based on a stall-speed jobs market and a slowdown in the economy during the first half of the year.

Mr. Powell still believes that tariffs are inflationary.

And when you read through his speech at the Fed conference at Jackson Hole, Wyoming, you see only the most grudging movement toward lower rates.

There was certainly no reference to market price indicators — such as gold, or the dollar, or commodity prices.

Frankly, there’s a subplot going on at the Fed that may be far more important than Mr. Powell’s monetary musings.

One of the Fed governors, Lisa Cook — a left-wing appointment by President Biden — has been criminally referred to the Department of Justice for alleged mortgage fraud regarding false statements on her primary residence.

And another allegation has been made that she lied about all that in her disclosure forms to serve on the Federal Reserve board.

President Trump has jumped all over this. A reporter asked him: “Are you going to fire Lisa Cook, the Fed governor,” over the mortgage allegations, “or if she doesn’t resign?” 

Mr. Trump replied: “Yeah, what she did was bad. So I’ll fire her if she doesn’t resign.”

If Ms. Cook is proven guilty, the president could surely fire her for cause — and that would cause an earthquake at the central bank.

According to a Wall Street and Washington watcher, Dan Clifton, Mr. Trump would get a new appointment to the Fed that would give him a 4-to-3 majority on the board of governors. That majority would also cause a major shakeup for the regional Federal Reserve bank presidents all across the country.

In other words, the fate of Ms. Cook could be the biggest determinant of the course of Fed policy over the next seven or eight months.

Unsurprisingly, Mr. Powell somehow failed to mention any of it in his speech.

From Mr. Kudlow’s broadcast on Fox Business Network.