Glenn explains his point (and not by saying it's a joke):
Sorry, blocking the interstate is dangerous, and trapping people in their cars is a threat. Driving on is self-preservation, especially when we’ve had mobs destroying property and injuring and killing people. But if Twitter doesn’t like me, I’m happy to stop providing them with free content."Driving on" is different from "Run them down." "Run them down" stresses hitting the people who are blocking you. "Driving on" is about prioritizing your own escape from danger. And Glenn obviously knows this and is saying that now:
I’ve always been a supporter of free speech and peaceful protest. I fully support people protesting police actions, and I’ve been writing in support of greater accountability for police for years.ADDED: The discussion at Twitter is collected at #FreeInstapundit.
But riots aren’t peaceful protest. And locking interstates and trapping people in their cars is not peaceful protest — it’s threatening and dangerous, especially against the background of people rioting, cops being injured, civilian-on-civilian shootings, and so on. I wouldn’t actually aim for people blocking the road, but I wouldn’t stop because I’d fear for my safety, as I think any reasonable person would.
“Run them down” perhaps didn’t capture this fully, but it’s Twitter, where character limits stand in the way of nuance.