Those who know John McCain best know he is short-tempered and flies into fits of rage. Is that the person we want to have his finger on the nuclear button? 

To Cindy McCain, in front of a group of Arizona reporters,

• "At least I don't plaster on the makeup like a trollop, you c*nt."

Sen. Bob Smith (R-NH)

• "His temper would place this country at risk in international affairs, and the world perhaps in danger. In my mind, it should disqualify him."

Sen. Thad Cochran (R-MS)

• "The thought of (McCain) being president sends a cold chill down my spine. He is erratic. He is hotheaded. He loses his temper and he worries me."

Sen. John Cornyn (R-TX) 

• 5/18/07: Things got really heated when Cornyn accused McCain of being too busy campaigning for president to take part in the negotiations, which have gone on for months behind closed doors. “Wait a second here,” Cornyn said to McCain. “I’ve been sitting in here for all of these negotiations and you just parachute in here on the last day. You’re out of line.”
  “F**k you! I know more about this than anyone else in the room,” shouted McCain at Cornyn.

Sen. Harry Reid (D-NV)

• 8/27/08 "I've served with the man 26 years. Do I have the ability to speak with experience about someone who has abused everyone he's dealt with? Someone who does not have the temperament to be president..."

Sen. Tom Harkin (D-IA)

• 9/7/08 "There have been times when he's just exploded. Look, around here, people lose their tempers once in a while. But it doesn't happen very often, and it usually happens in some contextual framework. A lot of times there's just not much of a contextual framework for his blowing up."

McClatchy 9/7/08:

• At age 2, McCain's tantrums were so intense that he'd hold his breath for a few minutes and pass out. His parents would dunk him in cold water to "cure" him, he wrote in his memoir, "Faith of My Fathers."
• "I have spent much of my life choosing my own attitude, often carelessly, often for no better reason than to indulge a conceit," he wrote. He conceded that some of his actions have been embarrassing, and "others I deeply regret."
• On election night 1986, then-Arizona Republican Party executive director Jon Hinz recalled, McCain was unhappy, even angry, even though he'd just won a U.S. Senate seat and his party had just made a virtually unprecedented sweep of state offices. McCain had hoped that night would help launch him as a national figure. Instead, when the 5-foot-9 senator-elect spoke at the Phoenix victory party, the podium was too tall. "You couldn't see his mouth," Hinz said. A furious McCain sought out Robert Wexler, the Young Republican head in charge of arrangements. "McCain kept pointing his finger in Wexler's chest, berating him," Hinz recalled. The 6-foot-6 Hinz stepped between them and told McCain to cut it out. "I told him I'll make sure there's an egg crate around next time," he said. McCain walked away angrily.
• About a year later [late 1987], McCain reportedly erupted again, this time at a meeting with Arizona's then-Gov. Evan Mecham, who was about to be impeached after being indicted on felony charges. Karen Johnson, then Mecham's secretary and now an Arizona state senator, recalled how McCain told Mecham that he was "causing the party a lot of problems" and was an embarrassment to the party. "Sen. McCain got very angry," Johnson recalled, "and I said, 'Why are you talking to the governor like this? You're causing problems yourself. You're an embarrassment.'" Johnson would go on to work at three different jobs over the next five years, and she said that each time, McCain would contact her boss and try to get her removed.
• Stories abound on Capitol Hill: how McCain told Senate Budget Committee Chairman Pete Domenici, R-N.M., how "only an a-hole" would craft a budget like he did.
• Or the time in 1989 when he confronted Sen. Richard Shelby of Alabama, then a Democrat and now a Republican, because Shelby had promised to vote for McCain friend John Tower as secretary of defense, and then Shelby voted against Tower. McCain later wrote how, after the vote, he approached Shelby "to bring my nose within an inch of his as I screamed out my intense displeasure over his deceit ... the incident is one of the occasions when my temper lived up to its exaggerated legend."
• Cochran recalled earlier this summer that he saw McCain manhandle a Sandinista official during a 1987 diplomatic mission in Nicaragua. Cochran told the Biloxi Sun Herald that McCain was talking, and, "I saw some kind of quick movement at the bottom of the table and I looked down there and John had reached over and grabbed this guy by the shirt collar and had snatched him up like he was throwing him up out of the chair to tell him what he thought about him or whatever." McCain said the incident never took place. "I must say, I did not admire the Sandinistas much," he told a news conference. "But there was never anything of that nature. It just didn't happen."
• In 1992, McCain sparred with Dolores Alfond, the chairwoman of the National Alliance of Families for the Return of America's Missing Servicemen and Women, at a Senate hearing. McCain's prosecutorlike questioning of Alfond - available on YouTube - left her in tears.
• Four years later [1996], at her group's Washington conference, about 25 members went to a Senate office building, hoping to meet with McCain. As they stood in the hall, McCain and an aide walked by. Six people present have written statements describing what they saw. According to the accounts, McCain waved his hand to shoo away Jeannette Jenkins, whose cousin was last seen in South Vietnam in 1970, causing her to hit a wall.
• As McCain continued walking, Jane Duke Gaylor, the mother of another missing serviceman, approached the senator. Gaylor, in a wheelchair equipped with portable oxygen, stretched her arms toward McCain. "McCain stopped, glared at her, raised his left arm ready to strike her, composed himself and pushed the wheelchair away from him," according to Eleanor Apodaca, the sister of an Air Force captain missing since 1967.