The U.S. is looking for trouble. Schools are opening and no children below 12 are vaccinated (except perhaps the few in clinical trials, which I hope are happening). These kids could spread COVID-19 fairly quickly. So here is an idea.
Approve emergency-use for 11-year-olds. Meanwhile monitor ages 11 and 12 for medical conditions that could be side effects. Continue to do this. Even an increase in some condition in age 11 after approval might indicate a special problem.
Then move to age 10 in a couple of weeks. And so on. This is something like a regression discontinuity design, but some of it could be based solely on comparisons after approval.
Apparently the FDA sees its duty as only toward the individual, not toward others that the individual might infect. But date from a procedure like this might give it enough information to act, in successive steps. Something is better than nothing.
Added 2/28/2022: Vaccines for children are still a problem in the U.S. Apparently the doses were too low, and the effects were either very small (ages 3 and 4, not approved yet) or wearing off quickly (ages 5-11, approved). So the same idea could be done with increased dosage. Now it seems we will have wait more months for more trials.
At this point, it seems that most people want to get back to "normal", despite the existence of continued spread that could be significantly slowed by greater and more effective vaccination. A return to normal would be more reasonable if we didn't have to worry about long covid, which is apparently a debilitating chronic condition, something like that caused by Lyme disease. As others remove their masks and continue to resist vaccination, some of us are just going to get better masks and continue to avoid indoor restaurants and any kind of public gathering, even though we, too, were hoping to some sort of return to normal.
