You aren't "sent" anywhere because of your major.
Your first two years out of CGA... you will be on a ship, or at a sector or at flight school. As a butter bar you have nothing to add to the liaison world, no experience, nothing.... learn operational stuff.... and see where it goes from there.
Some people will find the international training team out of Yorktown. That would be the first true international experience in a career. Beyond that, you're waiting for O-4. Coast Guard Activities Europe is in the Netherlands.
Being a government major won't give you a "leg up".... doing a good job at you first units and follow-on units will.
Where did I see the most of the world? I coordinated the Coast Guard's portion of a DOD outreach program. That took me to Greece, Spain, the United Kingdom, Germany, Colombia, Panama, Cuba (ok....GTMO), and I'm blanking on an island.... I liked each place.... but I really liked Greece and LOVED Colombia.
Being on a cutter, I only ever saw Cuba, Haiti and the Bahamas.... and mostly that was to return migrants.