B, because when Japan attacked China, China unified to fight a common enemy.
The Gulf of Tonkin Resolution <span> authorized the president to take "all necessary measures to repel armed attack" in Vietnam.
This resolution had significant consequences for the Vietnam War and beyond that time. In regard to the Vietnam War, it provided the justification for the president, Lyndon Johnson, to escalate US involvement in the war and magnify the number of US troops there by hundreds of thousands. In US foreign policy in general, it represented an increase of the power of the Commander in Chief (the president) to deploy troops without getting formal approval in advance from Congress.
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