Even though I am not a U.S. citizen, I would like to add my 2 cents, I think the U.S. should retaliate, whether it's a nation or a terrorist organisation, if it's a nation, however, war may not be required, a trade embargo can hurt a nation almost as much as a war, if both Europe and America locks out a country, imagine how much it would hurt, war may not be the ONLY solution, if it is a terrorist organisation however, such non-violent means as a lock-out or trades embargo will not be possible, it may be that violence is the only solution in that case.
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Worshipper of Tiax.
Wielder of the ancient Lawyer spells.
Member of the HADB clan.
Ally of the Fluffy Queen and the Dreaded Red Fluffy