[trainsplanes]

> I have never once seen a Japanese traveler required to produce any medical paperwork along with their passport (and I have flown a lot between both countries).

That's because a significant number of countries that require vaccines also require something called a "visa."

Visas have many years of history, and they're generally obtained beforehand. When applying for visas, you submit various documentation, pay a fee, and it makes your entry process much easier. When traveling first world to first world, visa checks for travel are generally waived. Going first world to anywhere not-first world, or in the opposite direction, usually requires some degree of a visa process.

[bruceb]

"First worlders" often are visa exempt when visiting non first world countries as well or visas are online and easily attainable.

Most tourist attracting countries that require visa for some, don't make one submit any medical info for both first world and mid tier countries.

[donw]

> That's because a significant number of countries that require vaccines also require something called a "visa."

Japan is not one of these.

[trainsplanes]

I have absolutely no clue why you're continuously focusing exclusively on Japan to avoid the fact that vaccine/immunization mandates have global precedents and they've existed forever at this point.

Japan might not mandate a certain vaccine. But if you're going to Bangladesh, Bangladesh does not in fact care about Japanese law.

For an example of how badly this works out, look up the UK guy who tried playing the sovereign citizen card in Singapore and pretending the law regarding disease spread doesn't apply to him. Spoilers: it did.