In a speech at George Mason University in Fairfax, Va., to unveil his American Recovery and Reinvestment Plan, Obama said there is plenty of blame to go around, from greedy Wall Street executives who made dangerous decisions to lax regulators to banks that did not take into consideration whether borrowers could make good on their loans to consumers who took advantage of easy credit to take out mortgages they could not afford.

"Reckless greed and risk taking … must never endanger our prosperity again," he said.

Obama, without including a pricetag, noted the scale of his plan is unprecedented, "but so is the scale of our problems." Taking a wait-and-see attitude has not worked, he said.

"Throughout history there have been years that simply rolled into the next without fanfare," Obama said. And then there are the years that come along once in a generation, the kind that mark a clean break from a troubled past and set a new course for our nation. This is one of those years."

Obama said the current crisis comes on the heels of an era of "profound irresponsibility."

"The result has been a devastating loss of trust and confidence in our economy," he said, adding that because the crisis is largely of our own making, "it's not beyond our ability to solve."

Obama warned it will take time to reverse the economic situation, making quick action imperative.

"We need to act boldly and to act now," he said. "This plan must begin today. It's not just another public works program."