(CNN) Hours after being sworn in as a freshman member of the 116th Congress, Michigan Democratic Rep. Rashida Tlaib told a crowd of liberal activists of her plans for President Donald Trump: "We're gonna go in there and we're going to impeach the motherf****r."

Tlaib was cheered by the crowd -- proving, in case there were still ANY lingering doubts -- that there is simply no way of being too anti-Trump for the Democratic base. Impeach Trump? Great! Call him names? Even better! Make those names curse words? Best!

But here's the thing: What Tlaib did on Thursday night might feel good for Democrats. It might make them feel as though they are regaining some of the fire and the fight they lost when Trump won in 2016. But it almost certainly is the wrong strategy if Democrats want to beat Trump in 2020.

Why? Well, put as simply as possible: Never wrestle with a pig because you both get dirty and the pig likes it.

To expand on that slightly: Donald Trump will say and do anything -- and I mean anything -- that he believes will work to his political advantage. There are no guardrails, there is nothing that he considers off-limits or out-of-bounds. You simply cannot go lower than he is willing to go.

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