There have been several treaties mentioned. The most commonly mentioned has evidently been broken by the ET's.
The Bible says the devil is a liar and the father of lies. Doesn't surprise me.
I think your assumptions related to the government using what exhotic weapons it has--those assumptions are greatly wrong.
It's long been standard SOP that whole categories of weapons would not see the light of day unless and until CONUS was attacked. And, it would likely take a wholesale attack at that.
And, if the elite rulers have decided to essentially trash the USA in the interest of the global government--not even then.
So, why super-weapons if the elites are going to deliever us to the ET's, Russians, and Chinese?
Sci-fi. Good and interesting sci-fi. Even thought provoking sci-fi. But sci-fi never the less.