Federal spending in general increases every year. But the fact is there discussion about cutting it. Your assertion was that no one talks about that is patently false. Half of all the sequester cuts are to defense. You are simply factually incorrect.
Here are some examples of restrictions: http://en.wikipedia.org/wiki/Treaty_on_the_Non-Proliferation_of_Nuclear_Weapons
http://en.wikipedia.org/wiki/Nuclear_weapons#Disarmament
http://en.wikipedia.org/wiki/START_I
http://en.wikipedia.org/wiki/START_II
http://en.wikipedia.org/wiki/START_III
http://en.wikipedia.org/wiki/New_START
http://en.wikipedia.org/wiki/Chemical_Weapons_Convention
All of this far exceeds any discussion on limiting WMD domestically.
The value of purchases of gun sales also steadily increase. While we have made efforts to curtail the most deadly weapons of war, guns are increasingly deadly every year. The bloodlust of gunners demands it. They aren't satisfied if they lack the ability to slaughter 100 babies in sixty seconds.
So once again, you are proven wrong. Guns grow in deadliness and killing capacity, while the worst weapons of war are regulated and decreased by international treaty.
You clearly have no moral issue with weapons that kill. Pretending that the machinery of death is only consequential if it is the result of a state military as opposed to a personal stash to be levied against defenseless babies, even American babies, is a vacuous argument.
Pacifists don't own guns. Nor do they defend their proliferation.