As a dutiful tourist, I sent a ton of postcards back to friends in the US while I was vacationing in Chile. I sent them from three different cities: La Serena, Santiago, and Easter Island (which ends up being Santiago anyway).
No one of my friends in the US has received one. However, friends in Canada and Japan got them within a week.
Who would be most likely to blame? Chilean postal officials? USPS?
Would the fact that the postage to the US from Chile was slightly less than it was to either Canada or Japan play a part in this?
All of my tour books have stated that Chile has an excellent postal system.
There is an International Postal Agreement that most countries participate in, which calls for postal reciprocity between countries.
This means that each country accepts mail with the local equivalent of a First-Class stamp on it, and then passes it on to the addressed country, which delivers it to the recipient. The first country recieved the money (you bought a Chilean postage stamp) and did part of the delivery work; the USPO did the rest of the delivery work but got no postage money.
I believe that there is an annual process where the postal services of the various countries ‘settle up’ with each other, taking into account how much mail went from Chile to the USA vs. how much went from the USA to Chile, the differences in postal rates between the 2 countries, difference in currency exchange rates, etc.
But that’s all between the 2 countries Postal Services; it should not affect delivery of your post cards.
What you’ve left out is the time that’s elapsed since their mailing.
I had a friend who sent postcards from the Czech Rep. in about 1995. They took about 5 weeks to get to California, and she beat them back by about 2 weeks.