The fastest growing country in pre-pandemic international tourism, for instance, was China, which has kept the virus in check by means of strict controls on travel. Now that the Delta variant is the dominant form of the virus globally, there is almost no chance of those controls being lifted any time soon. Other Pacific Rim countries are in a similar situation.

Australia, for instance, which used to be a tourist magnet, now has one of the hardest borders in the world. It’s extremely hard for non-citizens to enter, and even harder for citizens to leave.

New Zealand is considering allowing foreigners in next year, probably in the first instance from other countries with very low infection rates — but even that move would be highly controversial.

Vietnam currently isn’t allowing inbound tourism; when it starts, it will still insist on at least seven days of centralized quarantine — enough to dissuade all but the most avid travelers.