You are mischaracterizing what Rush (and I) are saying. He is NOT advocating that "the public let this drop." On the contrary, he is saying that this outburst perfectly reflects what the Democrats really believe. And he is saying that we (meaning all right-thinking Americans) should point this out again and again, repeatedly, until they cry "Uncle!" and then some. That hardly sounds like "letting this drop" to me.
Going without pushing for censure is letting it drop as far as Democrats are concerned. They are already starting to call discussion on the subject a diversion. Slowly bur surely statements like this will become acceptable and up for debate unless something is done.