I'm in the military and been to several nice countries. Is take 20k and party in Brazil or Peru or if all else fails there's always Australia.
You will not get far in Australia with $20k, however, the bot:dollar in thailand is well right now. If you want to make bank, being military, get over to Japan. Because the disasters, the yen rate sank...meaning COLA goes way up to compensate. Stay on base, dont convert your money to yen, and you're easily making over $10k more a year.
If i ever wanted to leave the country on a mid life binge, you'd find me in Egypt.
-FF