Only in the nation that you exist, and maybe not then, if you have been conquered at some point. The world is too large, and too diverse, for anyone to really unite everyone. Even a major threat that affects everyone, will not get seventy percent of the world to work togetherQuestion 115: How nationalized is identity in your world? (Do people buy into the imagined community? Has there even been attempts to create them so far, or is personal/regional loyalty common? In case national identity exists, has it gone so far as to create a civil religion? How is this represented?)
Imagined community - Wikipedia
Civil religion - Wikipedia