Here, apparently didn't get the tag earlier...

[quote=@catchamber]
As far as I know, General Electric has made nuclear weapons in the past.

Also, I'd be on board with the idea of nuclear powers formally spreading their arsenals with allies to ensure their sovereignty in an interdimensional contact scenario.
[/quote]

I'm for this too. This would be a little less political, and more unified in terms of sending some sort of international force (like a UN coalition of sorts). My reasoning being that regardless where that portal appears, everyone would more realistically react like "Holy shit guys! The hell is this?" Maybe later down the line when things settling, bases are established, ect, do we see countries trying to pull shit like Japan did in GATE. 

I'm also for having an alternate world for the Modern nations. I'm thinking along the lines of Ace Combat or something, just so we can have a bit more creativity.