Mr. Ryan chided President Obama for dismissing the recommendations of a deficit-reduction panel on which Mr. Ryan served and whose plans he opposed, and for seeking Medicare cuts that he too once sought.
He seemed to criticize the President for the closing of an auto plant in his hometown, Janesville, Wis., even though General Motors made the decision to shut the plant down in 2008, before Mr. Obama was elected. And he made misleading statements on many issues, including the President's health-care law and Mitt Romney's record in Massachusetts.
"The people of Wisconsin, like so many Americans, are still waiting for the President's imaginary recovery," said Brendan Buck, a spokesman for Mr. Ryan.
Mr. Obama did bail out the auto industry, and included money in the stimulus for "green" energy products.
One of Mr. Ryan's most pointed attacks on Mr. Obama was over the deficit.
"He created a new bipartisan debt commission," Mr. Ryan noted. "They came back with an urgent report. He thanks them, sent them on their way, and then did exactly nothing."
Left unsaid: Mr. Ryan served on that commission, and his opposition to its proposals helped seal its fate. The panel, dubbed the Simpson-Bowles commission, made several recommendations that Mr. Ryan ultimately opposed on grounds they would raise some taxes and fail to cut enough from health programs. His dismissal of the plan was seen as a key blow to its chance of success, since it soured other House Republicans on it.
In his critique of the President's fiscal stewardship, Mr. Ryan said: "It began with a perfect AAA credit rating for the United States. It ends with the downgraded America."
When Standard & Poor's lowered the nation's credit rating, it was in large part because of the standoff last year over raising the debt ceiling -- which had to be raised to pay for spending Congress had already approved.
The White House had asked Congress to simply raise the debt ceiling; Mr. Ryan and House Republicans balked at doing so without a deal on big spending cuts, leading to a prolonged standoff that took the nation to the brink of default.
In its statement explaining the downgrade, Standard & Poor's wrote that "the political brinksmanship of recent months highlights what we see as America's governance and policy-making becoming less stable, less effective, and less predictable than what we previously believed. The statutory debt ceiling and the threat of default have become political bargaining chips in the debate over fiscal policy."
Mr. Ryan also spoke out against the "$716 billion funneled out of Medicare by President Obama" without noting his own past budget plans had counted on the same savings, and pledged to protect Medicare without explaining how the Romney-Ryan plan would change it.
The Medicare debate is shaping up as a big election issue: Democrats say the Romney-Ryan plan to reshape Medicare would force future beneficiaries to pay more for health care; the GOP faults Mr. Obama for the $716 billion cut in future growth.
Mr. Ryan and Mr. Romney have proposed limiting the government's current open-ended financial commitment to Medicare. Under their plan, the government would contribute a fixed amount of money on behalf of each beneficiary, and future beneficiaries could use that money to buy private insurance or to help pay for coverage under the traditional Medicare program. It would apply only to people under 55.
Mr. Ryan's earlier budget plans called for capping the rate at which Medicare spending would grow -- which analysts from groups including the Kaiser Family Foundation have said would lead to higher out of pocket costs for future beneficiaries. The Romney campaign now says that its plan would work differently from Mr. Ryan's original plan, and that it would have the flexibility to raise the proposed cap on spending if it does not keep up with costs.
The $716 billion cut to Medicare that Mr. Obama made would reduce payments to health maintenance organizations, hospitals, and many other health care providers.