Days like today remind me that “the conservative movement” is, in fact, a movement. Together, we move toward a culture that is ever freer, fuller and more alive than the one we inherited, a culture that has as its touchstones timeless ideas that need no improvement but that has as its target human flourishing today.

The movement has its contradictions, but it’s unified by an irrepressible energy and optimism that trusts men to take care of themselves and each other and that embraces constitutional republicanism as the best system yet tried for the ordering of the affairs of men. Intuitively, conservatives understand that men, freed from chaos and freed for excellence, can create a culture that affirms truth, beauty and life.

Free, full, alive, irrepressible, excellent … Andrew Breitbart personified much of the best of conservative culture, and his loss is a forcible reminder of the worth of our cause. Who of those who ever met Breitbart — even just once or twice, as I did — would say he wasn’t flourishing? Who doesn’t think the world would be better if more of us were alive with that kind of passion and purpose?

His death demands mourning — from little bloggers like me to giants of the conservative movement like Sarah Palin to GOP leaders like Rick Santorum and Mitt Romney. So, we mourn as a movement.

Rick Santorum said he was “crestfallen.”

“Obviously, prayers go to him and his family and, wow, it’s a big shock,” the former Pennsylvania senator [said]. “What a powerful force. It’s almost — you think of anybody out there who’s more energy, and just, out there constantly, driving and pushing. What a huge loss, in my opinion for our country, and certainly for the conservative movement. My prayers go out to his family. I’m really sorry to hear it.”

Mitt Romney said he was “deeply saddened.”

“Ann and I are deeply saddened by the passing of @AndrewBreitbart: brilliant entrepreneur, fearless conservative, loving husband and father,” he tweeted.

Today, I feel as though both of these men — with whom I never quite agree enough to be able to support either for the GOP nomination without reservations — do actually speak for me. Like them, I’m crestfallen and deeply saddened. My prayers go out to Mr. Breitbart’s wife and children — and to the many journalists, writers and bloggers who will carry his banner forward as a part of the media empire he created.

Update: Newt Gingrich also tweeted in memory of Breitbart.

“Andrew Breitbart was the most innovative pioneer in conservative activist social media in America. He had great courage and creativity,” Gingrich wrote.

What I wrote of Romney and Santorum, I mean of Gingrich, too.