"By the time Congress is back in session and ready to take up gun control, Newtown will be fading a little in the public memory. It’s hard to imagine it now, but that’s what’s happened after every mass shooting of the last several years. The gun-rights advocates will be as single-mindedly impassioned as they always are, and the rest of us will be thinking of other things. But rallies and marches and demonstrations could remind those who’ve forgotten of what happened, serve to back up the members of Congress who want to do something about guns, and signal that there are numbers and votes on the other side as well. It’s simple—but it matters."