WASHINGTON — Standing before a nation on an economic precipice, President Barack Obama warned anxious Americans Tuesday night the U.S. faces a dire “day of reckoning” but can emerge ever stronger by pulling together, sharing sacrifices and confronting hard choices head-on.

“The time to take charge of our future is here,” Obama said, delivering his first address to a joint session of Congress.

Balancing candor and can-do, Obama acknowledged the battered economy, shaken confidence and the “difficult and uncertain times” that are all too real in homes and businesses across the country. But, he said, “The weight of this crisis will not determine the destiny of this nation.”

He said both political parties must sacrifice on favored programs while uniting behind his campaign promises to build better schools, expand health care coverage and move the nation to “greener” fuel use.

“Tonight I want every American to know this: We will rebuild, we will recover, and the United States of America will emerge stronger than before,” he said, according to excerpts released by the White House in advance of his speech.

Just five weeks after his inauguration, Obama was set to address an ebullient Democratic congressional majority and an embattled but reinvigorated GOP minority as well as millions of anxious viewers at home as a popular leader wielding significant clout to advance his agenda. Despite the nation’s economic worries and the lack of support for his plans from all but a few Republican lawmakers, Obama enjoys strong approval ratings.

But he spoke in the House as bad economic news continues to pile up. Some 3.6 million jobs have disappeared so far in the deepening recession, which now ranks as the biggest job destroyer in the post-World War II period. Americans have lost trillions of dollars in retirement, college and savings accounts, with the stock market falling nearly half from its peak of 16 months ago.

And new polls — some with his public support rising higher and others with it dropping — show that the political climate can be as precarious as the economic one. Aware that his and his party’s fortunes will suffer if he cannot right the economic picture, Obama sought to blend the kind of grim honesty that has become his trademark since taking office with a greater emphasis on optimism.

“Those qualities that have made America the greatest force of progress and prosperity in human history we still possess in ample measure,” he said. “What is required now is for this country to pull together, confront boldly the challenges we face and take responsibility for our future once more.”

The central argument of his speech was that his still-unfolding economic revival plan has room for — and even demands — simultaneous action on a broader, expensive agenda including helping the millions without health insurance, improving education and switching the U.S. to greater dependence on alternative energy sources. This is the big lift of his young presidency: bringing the public behind what are sure to be enormous outlays on contentious issues.

His hope was to begin to persuade the country that those longer-term items on his presidential agenda are as important to the nation’s economic well-being as unchoking credit and turning around unemployment numbers.

“The only way this century will be another American century is if we confront at last the price of our dependence on oil and the high cost of health care, the schools that aren’t preparing our children and the mountain of debt they stand to inherit. That is our responsibility,” Obama said.

New in office, he wasn’t charged with producing a formal State of the Union status report. But for all intents and purposes, that’s what it was: a night for the president to sketch out his priorities in a setting unmatched the rest of the year.

The gallery was to include a special section hosted by first lady Michelle Obama in which guests were selected to serve as living symbols of the president’s goals. Cramming the floor were to be the leaders of the federal government: Supreme Court justices, all but one Cabinet member — held away in case disaster strikes — and nearly every member of Congress.

Pre-speech, Wall Street was in a better mood than it had been in for days: Stocks were up after Federal Reserve Chairman Ben Bernanke said the recession might end this year.

Comments on Obama’s address came in early from Republicans, hours before he had uttered a word.

Louisiana’s young, charismatic governor, Bobby Jindal, who was delivering the televised GOP response to the Democratic president, exhorted fellow Republicans to be Obama’s “strongest partners” when they agree with him. But he signaled that won’t happen much, calling Democrats in Congress “irresponsible” for passing the $787 billion stimulus package that Republicans have criticized as excessive and wasteful.

“The way to lead is not to raise taxes and put more money and power in hands of Washington politicians,” Jindal said, according to excerpts of his remarks released by the Republican Party. “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?”

Jindal is considered a likely presidential contender in 2012.

In contrast to many State of the Union addresses by George W. Bush, Obama was emphasizing foreign policy. He was touching on his intention to chart new strategies in Iraq and Afghanistan and to forge a new image for the U.S. around the world even as he keeps up the fight against terrorism.

Obama declared that the budget request he is sending to Congress on Thursday will slash that deficit by at least half by the end of his term in 2013, mostly by ending U.S. combat in Iraq and eliminating some of Bush’s tax cuts for the wealthy. He said his budget officials have identified a total of $2 trillion in savings over the next 10 years, also including ending education programs “that don’t work” and payments to large agribusinesses “that don’t need them,” eliminating wasteful no-bid contracts in Iraq and spending on weapons systems no longer needed in the post-Cold War era, and rooting out waste in Medicare.

“Everyone in this chamber, Democrats and Republicans, will have to sacrifice some worthy priorities for which there are no dollars,” he said. “And that includes me.”

But he said this belt-tightening must not preclude increased spending in the areas he deems crucial.

“Now is the time to act boldly and wisely to not only revive this economy, but to build a new foundation for lasting prosperity,” he said.