Liberals are thrilled by the Mueller investigation these days. It seems like all upside to them. Their political opponents are being harassed day and night. Some of them may soon be indicted. The administration can barely govern with all the noise about Russia.

Robert Mueller is said to be a Republican – they always tell us that. But in effect, Robert Muller is doing the heavy lifting of the Democratic Party. If you’re a progressive who hates Donald Trump, this is like Christmas every single day.

Or is it?

Writer T.A. Frank has his doubts about that. Frank is no right-winger. He doesn’t like Donald Trump.

But he’s thought this through. In an insightful piece for Vanity Fair, Frank wonders if liberals will look back and consider the Mueller investigation worth doing. In response to criticism from the left, Frank notes this: "Trump's White House has pursued what is arguably the harshest set of policies toward Russia since the fall of Communism. Hardly something to celebrate. Yet nearly all the pressure, from the center-left as much as the right, is toward making it even tougher [on Russia].”

So the question is, is it really wise to risk war with a nuclear-armed power solely for short-term partisan political advantage? Is that a precedent you want to set, Frank wonders.

And then this, which ought to be printed and taped to the fridge in the kitchen of every Democratic political consultant in Washington.

"The weapons you create for your side today will be used by the other side against you tomorrow. Do we really want the special-counsel investigation to become a staple of presidential life? It's a creation with few boundaries on scope and a setup that encourages the selection of a suspect followed by a search for the crime, rather than the other way around."

Well, that’s a good point. Democrats are now telling us that Robert Mueller is somehow above the reach of government. Any executive branch oversight of his investigation qualifies, they tell us, as an impeachable offense.

In their telling, Mueller is something like a God-prosecutor, accountable only to himself. But the question is will Democrats be comfortable with this standard when the next independent counsel investigates the next Democratic president? And more to the point, what ever happened to representative government? Shouldn’t all federal employees answer to elected officials, who in turn answer to voters? Well, not anymore.

In the name of defending democracy, the left is weakening democracy. Democrats don’t seem to understand that now. They’re having too much fun watching their enemies suffer. But they will understand it. And likely they’ll deeply regret it.

Adapted from Tucker Carlson's monologue on "Tucker Carlson Tonight" on December 6, 2018.