Say it's 1968-69, right at the peak of the Anti-Vietnam movement in the West.
North Vietnam, and the Vietcong, in lue of the Tet Offensive of OTL instead decides to launch a domestic terrorist attack somewhere on the west coast of the United States.
Article 5 of the NATO treaty automatically activates. (See September 11th..)
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- What happens next?
- Would western Europe actually jump into the conflict to abide by NATO?
- Would France jump back in?
- Would NATO collapse if the allies refuse to fight in Vietnam?