In a blog post this morning, Dan Rather explained his comments from the weekend’s “Chris Matthews Show” and the controversy that surrounded them. On Sunday, Rather used the expression “he couldn’t sell watermelons if you gave him the state troopers to flag down the traffic” in explaining the position of President Obama’s opponents.

Rather, known for his “folksy” sayings, writes at The Huffington Post, “It’s an expression that stretches to my boyhood roots in Southeast Texas, when country highways were lined with stands manned by sellers of all races. Now of course watermelons have become a stereotype for African Americans and so my analogy entered a charged environment.” He adds, “I’m sorry people took offense.”

Perhaps even more interesting is Rather’s take on how the news spread in the new media landscape:

But what has caused this comment to “go viral” is the trumpeting of an online and cable echo chamber that claims the banner of news but trades in gossip, gotcha, and innuendo. Furthermore, even for those who brook no prejudice, when everything is condensed to 140 characters or a small YouTube clip, many people who got this “news” did so without any context, just a headline that popped up on their phone or inbox.

“What saddens me is what this experience has made all too clear,” Rather writes. “Much of what we call news, isn’t.”

More: TVNewser sat down with Dan Rather for a Media Beat discussion about the changes happening in journalism.