What gave president johnson the power to commit troops to vietnam without asking congress for a declaration of war?

a. gulf of tonkin resolution
b. southeast asia treaty
c. geneva accords
d. truman doctrine

The answer is actually A
the gulf of tonkin resolution was when a claim was made that a vietnamese ship fired at an american vessel therefore making a declaration of war valid

however it was later discovered that the incident never happened

johnson just needed an excuse to go to war