After winning my first game i decided to have some fun and nuke everyone. I don't however know how i can get the "Falling Out" Achievement.

Falling Out reads as follows:

"Nuke the capital of an Empire that was an ally at the turn beginning."

But Nuclear Missiles take a turn to arrive and you can not Nuke before breaking the Alliance. I tried to launch a nuke in the same turn i break off the alliance and start a suprise war, but this only got me the "Capital Punishment" ("Nuke a Capital") achievement, because well.. the nuke needs time to travel and you cant launch it before you declare war.

Is there something i am missing? This seems to be impossible to get.

I did the same thing.

Except i started a surprise war, targeted the nuke, THEN surrendered and got back into the alliance so that the Empire would be an ally at the start of the turn nuke lands.

HOWEVER, this didnt work lol, the nuke landed in the capital and fizzled out, doing nothing.

I'll be waiting for a tutorial, if that move aint it, ive got no idea.

Yes it seems like an oversight maybe. Though i didn't even think about your method, maybe we are still missing something that works.