> they were obligated to match the EU's by international treaty Nope. "We have to align to the more generous terms in territory X" is almost always one ration

> they were obligated to match the EU's by international treaty Nope. "We have to align to the more generous terms in territory X" is almost always one rationale offered for expansions, everywhere. There is no such treaty requirement. What the US is obligated to do by treaty is give everybody else's copyrights the same benefits their own get in their country. The reason this rationale is used is that it's cover to grow copyright indefinitely because you insist on "aligning" only with other people's more favourable terms, but of course in the process you also uprate the places where your terms were already most favourable, thus ensuring other countries with the same practice will likewise re-align, so this ping-pongs forever.