Some members of Congress hemmed and hawed in their support of or disagreement with the Tonkin Gulf Resolution. But Ernest Gruening was 100% committed to voting against the resolution from the start.

He said:

"I find myself in disagreement with the President's Southeast Asian policy […]"

and that the attacks in the Gulf of Tonkin were:

"inevitable […] consequences of U.S. unilateral military aggressive policy." (Source)

It's almost as though Gruening knew this was coming, knew that Congress would authorize the President to take action, and knew that he would be outvoted. It's interesting to note that Gruening had the foresight to know that this military engagement would involve much more than just Vietnam. He said:

"We are now about to authorize the President, if he sees fit, to move our armed forces not only into South Vietnam, but also into North Vietnam, Laos, Cambodia, Thailand…" (Source)

As history shows us, America did in fact commit to a bombing campaign in Laos and Cambodia in later years. Score one for prophet Ernest.

On a bit of a philosophical note, it is worth noting similarities and differences to other wars in American history. Gruening did not want American soldiers in Vietnam, and went as far as to say we were "sending our American boys into combat in a war in which we have no business, which is not our war" (source).

Most historians and Ponderers of the Past (that's an official title here at Shmoop, by the way) would agree that some wars are worthy, noble causes (for example, World War II). But a war like Vietnam has drawn heavy criticism for being wars where, as Gruening said, "we have no business" (source).

Such thought begs the question, when is it correct and dutiful to go to war?