But another explanation is simpler: Many Americans don’t realize that what happened in Puerto Rico is a domestic disaster, not a foreign one.

A new poll of 2,200 adults by Morning Consult found that only 54 percent of Americans know that people born in Puerto Rico, a commonwealth of the United States, are U.S. citizens. (Because Puerto Rico is not a state, they do not vote in presidential elections, but they send one nonvoting representative to Congress.)

This finding varied significantly by age and education. Only 37 percent of people ages 18 to 29 know people born in Puerto Rico are citizens, compared with 64 percent of those 65 or older. Similarly, 47 percent of Americans without a college degree know Puerto Ricans are Americans, compared with 72 percent of those with a bachelor’s degree and 66 percent of those with a postgraduate education.

Inaccurate beliefs on this question matter, because Americans often support cuts to foreign aid when asked to evaluate spending priorities. In our poll, support for additional aid was strongly associated with knowledge of the citizenship status of Puerto Ricans. More than 8 in 10 Americans who know Puerto Ricans are citizens support aid, compared with only 4 in 10 of those who do not.