Amity Shlaes: Demonizing business deepened the Great Depression. The White House can learn from Roosevelt's mistakes.

That's been a running theme this week. What brings back a crumbling economy is confidence, not just among businesses but also consumers. That's why tax cuts work when deficit spending doesn't. Deficit spending happens a year at a time and so it contains its own time limit. Tax cuts, especially ones without expiration dates like the Bush cuts, give businesses more confidence that it's safe to invest and hire. Now the Democrats will let those tax cuts expire and try to blame the resulting tax increases on George Bush. That's pure, Grade A, 100% demagoguery.