You can vote in U.S. elections from anywhere in the world.
If you live outside of the U.S. and meet voter eligibility requirements in your home state, you can register to vote by mail using the Federal Post Card Application (FPCA). This includes:
U.S. citizens who move to a new country, including expats
Students studying abroad
U.S. citizens working outside of the U.S.
This is right from the government website.
Not twist that around and claim you were right all along.