John McCain's team Monday piled pressure on his Democratic foe Barack Obama, after one of his top military backers said the Republican's Vietnam war heroism did not qualify him to be president.
On a day when Obama moved to address slurs against his patriotism, a new campaign row erupted over McCain's naval service, sparked by comments by NATO's former supreme commander, retired general Wesley Clark.
Clark, a former Hillary Clinton supporter who now backs Obama, said on Sunday he admired McCain's service, but suggested that record did not in itself qualify him to serve as president.
"He hasn't been there and ordered the bombs to fall, he hasn't seen what it's like when diplomats come in and say, 'I don't know whether we're going to be able to get this point through or not,'" Clark said on the CBS show "Face the Nation."
"I don't think riding in a fighter plane and getting shot down is a qualification to be president."
The comments opened a new dimension in the debate over whether Obama, 46, a first-term Illinois senator, has the necessary experience to be president.
McCain, 71, is offering himself as a veteran of national security and foreign policy questions who is best prepared to keep Americans safe.
McCain, a navy pilot shot down over North Vietnam and incarcerated in the infamous Hanoi Hilton jail, was asked about the comments during a campaign swing through Pennsylvania.
"I think that kind of thing is unnecessary, I am proud of my record of service," McCain said, adding that it was up to Obama to decide whether to respond directly to Clark's comments.
McCain's campaign however held a conference call with reporters, significantly cranking up the pressure on the Obama camp.
"I was utterly shocked when I saw this yesterday, that he would in a disrespectful way attack one of his fellow career military officers," said Republican Senator John Warner, a respected military expert.
Warner also sought to pressure Obama over Clark's comments.
"To the extent he had knowledge of this I find it an exercise of poor judgment to allow an individual like Clark ... to come in and do this attack."
Bud McFarlane, a former national security advisor to ex-president Ronald Reagan, also weighed in on the conference call.
"Senator Obama, some day may have the good fortune to be able to engage with foreign leaders, or to have become as well read as John McCain in history and in national security affairs, but it doesn't exist right now.
"For General Clark to portray John McCain as somehow unqualified is truly an unworthy comment that is astonishing to me."
Obama refered to the controversy indirectly during his speech in Missouri, saying that people should honor servicemen like McCain who had endured "physical torment" for their country.
His campaign later released a statement formally repudiating Clark's remarks.
"As he's said many times before, Senator Obama honors and respects Senator McCain's service, and of course he rejects yesterday's statement by General Clark," said spokesman Bill Burton.
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