Medicare does not cover health expenses overseas, but some Medigap policies and short-term travel medical insurance do. Pauline Frommer, editorial director of the Frommer's travel-information company, and John DiScala, a travel writer who goes by JohnnyJet on Twitter, both favor T-Mobile, which has a plan that allows free roaming and unlimited data in more than 100 countries. Travel experts are divided over whether President Donald Trump's proposed travel bans and anti-immigrant rhetoric will put Americans in more danger overseas. The Global Business Travel Association said it surveyed 176 U.S.