Now that Charlton Heston is stepping down after five years as chairman of the National Rifle Assn., it’s time to give him his due. In a perverse way, he was good for the process. The process of free speech, that is.When a Tim Robbins or a Sean Penn comes under attack, there is a dependable chorus of voices rising to their defense. On the other hand, the entertainment community is not exactly a bastion of support for the goals of the NRA. And Chuck Heston, who is a gracious man by nature, has not been a local folk hero. But he’s held true to his message. And until his recent retirement, he has also kept working. Whenever I encountered him, he was treated respectfully, even warmly, by his colleagues in the industry. Through it all, he was mind-bendingly wrong-headed, to be sure. Michael Moore may surely not have all the answers, but his basic theme in “Bowling for Columbine” was entirely valid. This country is armed to the teeth. The gun culture is predominant. Who can forget the brother of Terry Nichols, who, when asked if nuclear weapons should be available to everyone, responded, “No. There are a lot of nuts out there.” The nuts loved you, Chuck. Enjoy your retirement!