Not at all - when flying through Miami on a way to Bolivia in June last year, we had to get a full US visa (which caused us tons of problems due to company issu

Not at all - when flying through Miami on a way to Bolivia in June last year, we had to get a full US visa (which caused us tons of problems due to company issuing them for wrong country, making them invalid). Maybe it depends on airport design, but in Miami there is nothing stopping you from leaving the airport. In fact, we also experienced various issues with flights, and had to literally get out to check in area and chase airlines to take us (it is a long story, full of drama and missed flights due to external errors/issues). US is special in this, now we heed the advice of many - don't travel through US in any way, potential troubles are not worth it.