An endless war of limited intensity is worse, many Americans instinctively feel, than a time-limited war of unlimited ferocity. A crushing blow that brings an end to the war—like General Sherman’s march of destruction through the Confederacy in 1864-65—is ultimately kinder even to the vanquished than an endless state of desultory war.This Mead wants massive Israeli retaliation against Gaza regardless of civilian casualties and thinks Americans would agree with him. He appears to be under the impression that not much happened in the US Civil war prior to Sherman's march, and that single crushing blow was all that counted.
The reality was that it took years of unlimited ferocity to win the Civil War. The side that had better logistics won the war, and Sherman's march was a logistical success, living off the land while destroying its ability to support the enemy. Not a lot that parallels Gaza here.
More broadly, I think there's little evidence that shock and awe achieves its psychological goals. The British, German, and Japanese people didn't break over the bombing raids. Psychology does have its place - the Doolittle Raid heightened American morale and convinced the Japanese to make the stupid mistake of withdrawing carriers to defend the home islands and to undertake the high-risk attack on Midway. Brutality by itself, though, won't win wars.
Tangentially related: Brad DeLong has been live-blogging a history of World War II. Definitely worth checking out.