Banning travel isn't a magic cure-all that guarantees zero cases, it just lowers the initial caseload. That's extremely important because exponential growth is extremely slow in the beginning -- it takes as long to go from 1 to 100 as 100 to 10,000. If banning travel reduces 100 starter cases to 1, you double the time you have.

Some commenters on this post are having a hard time acknowledging this aspect. I think every little bit helps, this included

It won't. Screening all arrivals is helpful, but just shutting down travel is going to end up creating a whole new class of problems.

Medical officers (and Italy) tell us that screening arrivals doesn't help.

I was thinking more for data gathering purposes and so on before the healthcare system collapses under the weight of exponential growth. But I take your point.

Every little bit also has a cost, and it's possible for the cost to outweight the benefits, especially when a decision is made without even considering the cost.

True and fair point with which I agree. I don't know all the considerations that went into this decision but I lean towards supporting such plans that limit unnecessary chances for exposure

Problem being, best information is there is no solid numbers on initial case load in the US, for structural reasons. So while your argument may be correct, it may be too late for this to make a difference (perhaps with equal likelihood, but we don't know.)

Yeah, I'd agree with that. At this point it would help a tiny bit, but only because it slightly decreases links between people, like a social distancing measure does.

> it just lowers the initial caseload

If it's done in time to prevent the bulk of that initial caseload, which is almost certainly not the case here.

I beg to differ. US was the first major country to ban travel from China. Other countries only followed suit after. South Korea, Japan, France, Germany and Italy never did, and see where they are now.

Please do not spread disinformation: Italy banned direct flights from China pretty quickly too.

It did not matter, because patient-0 in Europe was a German. It’s now accepted that the virus arrived by crossing the Alps in some sort of Euro-business trip, not directly from China.

So banning international travel could have at least stopped it from reaching Germany. I think you are making his point while arguing on a technicality. I see no conceivable way that the economic loss of tourism or "business trips" is worse than what is about to go down in Europe.

The infection in Germany happened mid-January, when the Chinese had not even fully admitted to the problem. Chances are it had already reached all continents by the time any travel ban was even considered.

Unless you can read minds, these things happen very quickly now that the world is a global village.

> is worse than what is about to go down in Europe.

It's going down in the US too! We're merely a few days behind. If we had no cases, or a few contained clusters, then this would be an arguably useful policy. We have multiple uncontained outbreaks already, and have yet to enact meaningful policies to contain them.

It's too late. All this ban does is try to shift blame.