Many countries require tourists who enter the country on a regular visa that their passport be valid at least six more months from the date of leaving the country.
What’s the deeper meaning behind this rule? What makes immigratio officials be concerned about tourists entering, and leaving, their country on a passport which is going to expire in less than a half year’s time?
This is a wild-ass guess of the first order, but I can imagine that it might have originated in wanting a good safety margin of a few months in case they got sick or injured or ran out of money and were unable to travel for a while.
Bear in mind that if you let someone into your country, you also need to make sure they can leave again. So not only do you need to be OK with them leaving before their passport expires, anyone you try to pass them on to also need to be OK with the time left after their stay in their country. Otherwise you end up with unseemly squabbles at borders.
“I’m not letting this person into my country, their passport is about to expire and they might not leave”.
“Well I’m not letting them stay in MY country any longer, their passport is about to expire”.
This whole system sort of evolved back in the days of ships and so on, when you might be in transit for a while and/or have to cross other countries to get home and things had to be done by post. So six months seems sort of sensible.
Often tourist visas can be extended to up to six months.