They're one and the same. God set this trial because humans summoned demons in the first place, but they only did it to accelerate the War for the Throne of Bel, so that they could... endorse the demon they wanted to win, so they could get that demon to kill God for them. The idea was that this way, humans wouldn't ever have to deal with another one of God's trials. And, um. The previous trials God sent to us were... "Splitting the common primal tongue" into different languages, and then flooding the Earth and making humans restart from scratch, at least those are the stories I know. There might even be more.

[Again, he rubs the back of his head.]

I'm not sure how the government started working with the angels to begin with. There's a good chance the angels threatened them or something.