There does seem to be a false veneer of "patriotism" on 9/11, but perhaps it's an opportunity to separate nationalism from patriotism. Perhaps self-sacrifice for others is patriotism. Helping neighbors, other Americans, humans even when there is a cost to oneself (& on 9/11 great cost) is patriotic

But I don't think that's the lesson - the people most loudly being "patriotic" also assert the acceptability or correctness of their behavior even if (or particularly when) they're being a-holes. If you're using the flag to destroy the principles for which it stands, you've lost the plot.