Further imagine that Missouri
No, no - this is far too simple. Imagine that Missouri does this:
1) Missouri applies to join Mercosur (South American trade bloc), or the EU
2) Missouri regularly receives fuel and electricity supplies from Illinois at subsidized rates, while transferring other volumes of energy on to Kansas, which still remains a part of the Union. One fine day Missouri decides that's not enough, and their prime minister - through the company she owns - begins to illegally siphon off Illinoian gas.
3) Missouri applies to join the Shanghai Cooperation Organization, and at least two times a year - through its foreign minister - requests S-400 systems from Russia to protect Missouri's airspace from the rest of the United States.
4) Missouri begins to claim that George Washington was a native of Missouri, and also begins referring to itself as America, while calling the remaining states the Colonial States of America.
5) The rest of the United States looks at everything Missouri is doing, and says: "Stop, before we rape you." Missouri's response is: "Try your best faggots! Ahahahaha - Brazil will protect me!"