Can't see any problem in taking mince pies to the US. Should be fine.
And just in case anyone is thinking of taking Christmas Crackers - please note they must be packed in your suitcase and you can only have a maximum of 2 boxes. They can't be hand made, and must be bought from a reputable store (I seem to recall
adrianjc32 mentionining Fortnum & Mason


).
Please remember cases must be no more than 32kg and still only one piece of hand luggage through Security. You'll be surprised how many have forgotten both those things this week!!!