What is to counter? You say they should join. We say there are many things to show support.
Your argument that the ONLY way to show support is to "put up or shut up;" join or you really aren't supporting the way...well, that is just piss-weak.
I also think it is pretty piss-weak for you to defend John Kerry. Here is a Vietnam War Veteran - hero in some people's eyes - who said and did the following:
On April 22, 1971, Kerry became the first Vietnam veteran to testify before Congress about the war, when he appeared before a Senate committee hearing on proposals relating to ending the war. Kerry began with a prepared speech, in which he presented the conclusions of the Winter Soldier Investigation, where veterans had described personally committing or witnessing war crimes.
Controversially referring to US servicemen in Vietnam as having been sent "to die for the biggest nothing in history," Kerry alleged that the military had "created a monster" in the form of violence-prone American soldiers, and recounted that soldiers had personally recollected stories of having "personally raped, cut off ears, cut off heads," of Vietnamese citizens and rampaging across Vietnam "[razing] villages in fashion reminiscent of Genghis Khan".
Most of Kerry's testimony addressed the larger policy issues.
Kerry expressed his view that the war was essentially a civil war and that nothing in Vietnam was a realistic threat to the United States. He argued that the real reason for the continued fighting was political purposes: "Someone has to die so that President Nixon won't be, and these are his words, 'the first President to lose a war.'" That conclusion led him to ask: "[H]ow do you ask a man to be the last man to die in Vietnam? How do you ask a man to be the last man to die for a mistake?"
The day after this testimony,
Kerry participated in a demonstration with 800 other veterans in which he and other veterans threw their medals and ribbons over a fence at the front steps of the U.S. Capitol building to dramatize their opposition to the war. Jack Smith, a Marine, read a statement explaining why the veterans were returning their military awards to the government. For more than two hours, angry veterans tossed their medals, ribbons, hats, jackets, and military papers over the fence. Each veteran gave his or her name, hometown, branch of service and a statement. As Kerry threw his decorations over the fence, his statement was: "I'm not doing this for any violent reasons, but for peace and justice, and to try and make this country wake up once and for all." Some have questioned whether he gave up his own medals or just his ribbons during the demonstration at the Capitol. Tom Oliphant has gone on record supporting Kerry's account.
http://en.wikipedia.org/wiki/John_Kerry#Controversy_over_military_service_and_awards
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Now there is a role model.
Piss-weak.