For your edification, "Screaming" Howard Dean has provided a handy definition of the word 'opportunist':
While we honor McCain's military service, the fact is Americans want a real leader who offers real solutions, not a blatant opportunist who doesn't understand the economy and is promising to keep our troops in Iraq for 100 years."
From Wikipedia:
John McCain's capture and imprisonment began on October 26, 1967. He was flying his twenty-third bombing mission over North Vietnam, when his A-4E Skyhawk was shot down by a Soviet-made SA-2 anti-aircraft missile over Hanoi.[34][35][36][37] McCain fractured both arms and a leg,[38] and then nearly drowned when he parachuted into Truc Bach Lake in Hanoi.[34] After he regained consciousness, a mob gathered around, spat on him, kicked him, and stripped him of his clothes.[39] Others crushed his shoulder with the butt of a rifle and bayoneted him in his left foot and abdominal area; he was then transported to Hanoi's main Hoa Loa Prison, nicknamed the "Hanoi Hilton" by American POWs.[39][40]
Although McCain was badly wounded, his captors refused to give him medical care unless he gave them military information, beating and interrogating him.[39] Only when the North Vietnamese discovered that his father was a top admiral did they give him medical care[39] and announced his capture. His status as a POW made the front pages of The New York Times[41] and The Washington Post.[42]
McCain spent six weeks in the Hoa Loa hospital, receiving marginal care.[34] Now having lost 50 pounds, in a chest cast, and with his hair turned white,[34] McCain was sent to a different camp on the outskirts of Hanoi[43] in December 1967, into a cell with two other Americans who did not expect him to live a week; they nursed McCain and kept him alive.[44] In March 1968, McCain was put into solitary confinement, where he would remain for two years.[39]
In July 1968, McCain's father was named commander of all U.S. forces in the Vietnam theater.[2] McCain was immediately offered a chance to return home early:[34] The North Vietnamese wanted a worldwide propaganda coup by appearing merciful, and also wanted to show other POWs that elites like McCain were willing to be treated preferentially.[39] McCain turned down the offer of repatriation; he would only accept the offer if every man taken in before him was released as well.[45] McCain's refusal to be released was even remarked upon by North Vietnamese senior negotiator Le Duc Tho to U.S. envoy Averell Harriman during the ongoing Paris Peace Talks.[46]
In August of 1968, a program of severe torture methods began on McCain, using rope bindings into painful positions, and beatings every two hours, at the same time as he was suffering from dysentery.[39][34] McCain made an anti-American propaganda "confession" that said he was a "black criminal" and an "air pirate".[34] He has always felt that his statement was dishonorable,[48] but as he would later write, "I had learned what we all learned over there: Every man has his breaking point. I had reached mine."[39] His injuries left him permanently incapable of raising his arms above his head.[49] He subsequently received two to three beatings per week because of his continued refusal to sign additional statements.[50] Other American POWs were similarly tortured and maltreated in order to extract "confessions",[39] with many enduring even worse treatment than McCain.[51]
And, of course, what McCain actually said about 100 years in Iraq:
McCain never actually went so far as to call for a century-long occupation. Rather, in response to a New Hampshire town hall questioner who asked about President Bush’s statement that U.S. troops could be in Iraq for 50 years, McCain interrupted and said, “Make it 100.”
“We've been in South Korea … we’ve been in Japan for 60 years,” he continued. “We’ve been in South Korea for 50 years or so. That would be fine with me. As long as Americans are not being injured or harmed or wounded or killed, that’s fine with me. I hope that would be fine with you, if we maintain a presence in a very volatile part of the world where Al Qaeda is training, recruiting and equipping and motivating people every single day."
Indeed, Screamin' Howie did define the word opportunist quite well. In fact, Howie's picture should appear right next to that word in dictionaries everywhere.