Individual actions to enforce norms often costs more than the individual infringements. Arresting, prosecuting and rehabilitating someone who commits property crime could cost many tens of thousands of dollars. It's worth it in the long-run, though, despite game-theoretic oversimplifications, because it reduces crime in the long run.

(Almost) everyone agrees that protectionist policies are directly harmful to America's economy. I wonder if people might be more willing to accept them as tools to encourage change in other countries behaviour if they were sold better, though, or sold by someone else.