The Times Square bomber showed in court how "useful" such an oath is. He proudly declared in open court that he took the loyalty oath when he received US citizenship, but "didn't mean it". All such an oath does is make prosecution and revoking citizenship easier AFTER THE FACT (in other words, after the damage is done). How useful is that?
No change in medical status among Jerusalem Gay Pride stabbing victims (Haaretz)
from the article: Labor expects new settlement freeze as payoff for loyalty oath