Mike Kinsley wrote a famous essay in the New Yorker a few years ago positing the length of one’s life as the ultimate footrace.  “The only competition that matters, in the end, is about life itself. And the standard is clear: ‘Mine is longer than yours’ ” 

Conservative media publisher and activist Andrew Breitbart died Thursday at the age of 43. (Kathy Willens/AP)

I realize that in the lifespan contest, he who lasts wins, but I like to think the way a person affects the world is a far greater measure of a life’s value than his accumulated time on Earth. Of the two quantifiable qualities, we have very little control over when we die, but we have everything to do with our impact.  

Mortality is heartless.  Andrew Breitbart,  the right-wing political commentator, Internet savant and accomplished flamethrower, was felled by an apparent heart attack Thursday while taking a walk in the Westwood section of Los Angeles.  

His fire burned brightly but by any measure of longevity, exceedingly briefly.  Breitbart, who ran an eponymous blog empire beloved by social conservatives, was only 43.  In right-wing circles, an ideological tactician of his talent has not been snuffed out so early in life since chairman of the Republican National Committee and political operative Lee Atwater died in 1991 at 40. Both men died young, but before they did, they had a profound effect on the way conservative social values became part of the national conversation.

Social values aside, having both impact and stamina is the real prize in the longevity competition. The Rolling Stones band has been performing 50 years, and its current members appear to to be hearty examples of both impact and endurance.  

Another British invader — Monkees front man Davy Jones, who crooned “Daydream Believer” to legions of swooning little girls in the 1960s — died this week at 66. He was the first of his former bandmates to go, and his death sparked tremors of nostalgia among fully adult women recalling Marcia Brady’s prom night.

Jones died relatively young, but even he had 23 more years than Breitbart. To the political lightning rod's family and friends I convey condolences. His survivors include his wife, Susie, four children under 10, his parents and his mother- and father-in-law.  I doubt it is much comfort to his family, his many friends or his ideological followers, but they can at least feel certain that Breitbart had an enormous impact

Liberal causes that he battled against have lost a formidable foe. One measure of Breitbart’s effectiveness is the number of tasteless grave-dancing posts by his opponents that appeared on news sites  when his sudden death was reported.  

As rude as it is to speak ill of the dead, Breitbart was a political combatant, and I doubt he’d be terribly disturbed by the posthumous jeers. (He engaged in the practice himself at times).

His legacy includes disenfranchised Americans no longer aided by ACORN, farmers no longer assisted by Shirley Sherrod’s Agriculture Department program and screaming attacks against “filthy freak” student protesters. I know he didn’t expect to die so young, but he’d have been proud of his impact.