Tim O'Brien suspects that serving in Vietnam has had a weighty influence on the world views of former Senators Chuck Hagel and John Kerry. O'Brien is the author of the Vietnam-era classic "The Things They Carried."
"Aging and positions of power can influence a psyche as much as an experience such as Vietnam," O'Brien says. "But in Hagel's case, for example, he was not only in Vietnam, he was in Vietnam as a sergeant, as an enlisted man. And both men, both Kerry and Hagel, saw combat."
The experience of seeing war up-close, O'Brien says, no doubt "seeped into the bones" of the former senators.
O'Brien says he's mystified when Hagel and Kerry are chastised for being "too careful" when contemplating the use of US military force.
"When one of these men is being criticized as possibly too cautious, I want to yell at the top of my lungs, 'How can one be too cautious? You can't be too cautious!'"