Smirking at your discomfort is not a nice husband trait. That's him being a dick. He knows you don't like it and is now rubbing it in your face to show that he won't stop and doesn't care about your feelings. Doing in front of his family is a double power move.

I'd also be afraid of having kids with him after this comment, not just because he's being a jerk, he's now laid the groundwork for your MIL who hates you to treat you however she wants without consequences. What if she tries to turn the kids against you, you say something, and Mr Big Shot decides to lay down the law and "make your family pay" or whatever (which is big braggy talk meaning he's going to sct like an insufferable dick, but honestly he's almost there already.)

I'm so sorry for his behavior. I want to say throw the whole man away, but my more realistic advice would probably put him on divorce probation and let him know that if doesn't stop this, you're done. Look for other red flags of disrespect as well, and know that you do not deserve this and it's not normal. Keep calling him out on his bs.