strange messages

[civi_fan]

hi, im kind of confused here, i was playing civilization 4 yesterday, and when i got in the game , a message appeared saying "washington wants to join our glorious expanding empire " and then the options "install a new governor and so on..." but... washington is my capital, and it was already mine. now, the little icon on washington turned a little redish, you know, where the numbers are,

what does this mean???