Depends really, I guess since you are asking the question the enemy doesn't have enough nukes to simply plaster you with a load more if they miss.
Unless the city has some vitally (and I mean vital) important production facilities then I save the soldiers. 1M civvies out of 70M population isn't much, the civilian population will bounce back pretty quickly. Considering our current armed forces stand at about 250K then 4M would be a massive, massive loss, 16 times our current military manpower, that's something you don't come back from.
Unless the city has some vitally (and I mean vital) important production facilities then I save the soldiers. 1M civvies out of 70M population isn't much, the civilian population will bounce back pretty quickly. Considering our current armed forces stand at about 250K then 4M would be a massive, massive loss, 16 times our current military manpower, that's something you don't come back from.