So are you arguing that disease isn't a risk, or just that there is never a need to have border control to deal with it? It is a risk, one that we can and do t

So are you arguing that disease isn't a risk, or just that there is never a need to have border control to deal with it? It is a risk, one that we can and do take into consideration. Anyone seeking to be a permanent resident in the U.S. is required to have certain vaccinations. That requires a certain level of border and immigration control to enforce. Having a well-functioning medical system is good, but won't help much if your dealing with the spread of disease that isn't easily treatable. Or rather, quarantine is part of a well-functioning medical system. And yes, shutting down travel to/from certain countries experiencing a serious epidemic has been a real consideration in the past. Look, I'm not saying "shut down the borders". All I'm saying is that completely open borders are impractical and ignores real risks.