Quoted from Luckydogg420:In order to be a Christmas movie, and not just a movie that takes place during Christmas time. Christmas must be integral to the plot and not just something happening in the movies world.
Die hard is absolutely a Christmas move.
The plot requires that everything happens during Christmas otherwise the movie wouldn’t work. They needed an excuse to have reduced security in the building while there was still enough employees to create a hostage situation so that the FBI would kill the building power. So they could drill into the vault. The only reason Bruce Willis is in that building is because of a Christmas party.
If you remove Christmas from Lethal weapon the movie remains the same, but if you remove Christmas from die hard the movie falls apart.
Excellent summation. I was going to comment but you said it all.