David Farrell on the Big Dig. I'm late in getting to this, but I want to call your attention to some online commentary by former Globe columnist David Farrell, who observes that the entire Central Artery/Tunnel Project never would have been necessary if Tip O'Neill and Michael Dukakis hadn't blocked construction of the Southwest Corridor and the Inner Belt.

(What Southwest Corridor and Inner Belt? Well, that's Farrell's point.)

A couple of counterarguments: (1) it wasn't all Democrats, as Republican governor Frank Sargent had a lot to do with the no-new-highways decision; (2) those massive highway construction projects would have destroyed entire neighborhoods, and thus there were good reasons for canceling them.

Still, Farrell reminds us of the law of unanticipated consequences.