Blugold Matt,
I don't think McCain's stance comes from a desire to project a false machismo. To whatever extent he has changed his positions, he has never changed his fundamental persona. He had the same position in 2000, as evidenced by him turning it down after winning New Hampshire. And I think he understands the extent to which we value stable leadership. I think it comes from a fatalism that is acquired after spending 6 years in a prisoner of war camp.
Serious presidential candidates have come to grips with the idea that their public profile is raised to such a point that they can be killed anywhere at anytime. The Secret Service is the best trained and best equipped security team in the history of the world. But they couldn't stop Oswald (or whatever hair-brained conspiracy you can conjure up) from killing Kennedy in Dallas. They couldn't stop Hinckley from shooting Reagan. A determined assassin, who is either very prepared or very lucky, can kill a candidate or president and there is nothing we can do to stop it.
Being a prisoner of war, where your fate is entirely in the hands of your captors and you have that same powerlessness, likely fuels McCain's view on this matter. It gives him a fatalism about being able to prevent a determined man from ending his life. I'm sure that McCain will still have the Secret Service investigate any threats and provide protection for his family -- President McCain's* daughter would have some new friends at school -- but how does having a massive security detail of 50 SUVs prevent the protectee from getting killed? The article makes clear that he isn't waving off all protections. He is just saying that it is overkill and that all the protections in the world don't protect you from a sniper. I think it is an interesting view.
CS
* -- I just like typing President John McCain. It sounds so much better than President Hillary Clinton or President Rudolph Guiliani.
Beach Boys -- Heroes and Villains
The Clash -- Living in Fame
