"In other words, we have lived through an era where too often, short-term gains were prized over long-term prosperity, where we failed to look beyond the next payment, the next quarter, or the next election," he told the packed House chamber tonight.

The televised speech was a sequel to his inaugural address, where he called for a "new era of responsibility." But after trying to charm Republicans for weeks, Obama's speech was also a feisty declaration that he will move forward on health care reform, climate change legislation and tax reform - with or without their help.

"The time to take charge of our future is here," he said.

Obama rekindled the theme of responsibility as he urged tougher regulations of Wall Street, reforms to get banks lending again and immediate action on neglected issues, including fixing the long-term solvency of Social Security and Medicare.

The tough love was greeted warmly by many lawmakers, who said the nation's economic troubles had created the perfect opening for Obama's sober call for tackling big challenges.

"The American people understand that we've been living beyond our means for quite some time. They want someone to be straight with them," said Rep. Mike Thompson, D-St. Helena, one of the conservative House Blue Dogs who's urged a return to fiscal responsibility. "They are not only ready for this, they are hungry for it."

Obama weaved the theme of responsibility throughout his speech as the underpinning of his agenda. He said it was crucial to let the Bush tax cuts for American families earning more than $250,000 expire to "save our children from a future of debt." The comment elicited applause from Democrats, but stony silence from Republicans.

He promised to do everything in his power to get the nation's banks lending again - including spending more taxpayer money - but vowed to ban bank executives from using the money to "pad their paychecks or buy fancy drapes or disappear on a private jet."

"Our job is to govern with a sense of responsibility," he said. "I will not spend a single penny for the purpose of rewarding a single Wall Street executive, but I will do whatever it takes to help the small business that can't pay its workers or the family that has saved and still can't get a mortgage."

Obama scolded lawmakers of both parties for failing to take on energy independence with a sense of urgency. He called on Congress to pass a climate change bill that "places a market-based cap on carbon pollution and drives the production of more renewable energy."

He also said the nation can no longer bear the crushing costs of health care, citing premiums that gone up four times as fast as wages over the last eight years. He said would bring Democrats, Republicans, health care experts and interest groups to the White House next week to begin crafting solutions.

Obama also called for more money for education, but also more reform, saying he would push for innovations like merit pay for teachers. He lectured high school drop-outs, saying, "It's not just quitting on yourself, it's quitting on your country."

Following up on his fiscal responsibility summit Monday, Obama pledged that he would try to slash the deficit, estimated at more than $1.2 trillion this year, in half by the end of his four-year term. He pointed out that he was inheriting the deficit, a shot at former President Bush.

But even his supporters said Obama must be careful as he talks of the need for fiscal restraint, not to exacerbate the problem with costly programs like health care - unless it's matched with reforms to trim long-term spending or raise new revenues.

"The last thing we should be doing is to expand health care entitlements based on a system that is badly broken and that could bankrupt America if we don't fix it," said David Walker, the former U.S. Comptroller General, who attended Obama's fiscal summit.

Republicans see Obama's appetite for big government programs as his Achilles heel. Louisiana Gov. Bobby Jindal, who gave the GOP response to Obama's speech, criticized the president's $787 billion stimulus package as a plan that would leave the country saddled with more debt.

"Who among us would ask our children for a loan, so we could spend money we do not have, on things we do not need?" said Jindal, who's seen as a possible 2012 presidential rival to Obama.

Obama, in his speech, responded with a historical argument, claiming that times of crisis called for major government intervention. He pointed to the construction of nation's railway system during the civil war and the post-World War spending on the GI bill as examples of wise investments.

"History reminds us that at every moment of economic upheaval and transformation, this nation has responded with bold action and big ideas," he said.

Obama, seizing on his high public approval ratings, is hoping to drive an ambitious agenda through Congress this year while he still commands strong public support.

A new Washington Post-ABC News polls showed that 68 percent of Americans approve of his job performance, higher than the ratings for Democrats in Congress (50 percent) or Republicans (38 percent.) The poll also found that 73 percent felt Obama was trying to find compromise with Republicans, while only 34 percent felt the GOP was doing the same.

San Jose Democratic Rep. Mike Honda, said Obama set the right tone by being realistic about the severity of the crisis, but also offering reasons for optimism.

"Obama has the ability to talk about what people see all around them. ... The economy is weakening, not only here, but globally," Honda said. "He can speak to people's shaken confidence, saying, 'We've had challenges before as Americans and we have faced them. We rolled up our sleeves and dealt with it.' "

E-mail Zachary Coile at zcoile@sfchronicle.com.