Republican Rick Perry, the conservative governor of Texas, on Saturday declared himself a candidate for US president with a blistering attack on Democratic president Barack Obama.
"I realise that the United States of America really is the last great hope of mankind," he said, as he accused Mr Obama of imperilling America's standing in the world with "disastrous economic policies" and the "incoherent muddle that they call foreign policy."
Delivering a speech to about 700 conservative activists in South Carolina, Mr Perry, 61, touted his job creation record in Texas and promised to reduce taxes, business regulations and the overall role of government in people's lives. He said leaders in Washington have lacked courage an Mr Obama's policies have "prolonged our national misery, not alleviated it."
"Mr President, let us tell you something. You cannot win the future by selling America off to foreign creditors. We cannot afford four more years of this rudderless leadership," he said.
Mr Perry's entry shakes up the race for the Republican nomination to face Mr Obama in the November 2012 general election. Opinion polls indicate Mr Perry is already close on the heels of former Massachusetts Governor Mitt Romney, the early Republican front-runner.
The Texan governor, who caused a stir in 2009 when he openly pondered his state's secession from the United States, was sharply critical of what he called an overbearing federal government.
"As Americans we realise that there is no taxpayer money that wasn't first earned by the sweat and toil of one of our citizens," said Mr Perry, drawing a loud round of cheers and applause from the hundreds of people who packed into a Charleston hotel to hear him speak.
"That's why we reject this president's unbridled fixation on taking more money out of wallets and pocketbooks of American families and employers and giving it to a central government," he said.
"Spreading the wealth punishes success while setting America on course for greater dependency on government."
Mr Perry's candidacy could steal support from fellow conservative Tea Party favourite Michele Bachmann, replacing her as Romney's top rival and potentially bridging the gap between the party's establishment centre and right-wing activists.
The three-term Texas governor is an opponent of abortion rights and gay marriage. He is considered a strong fund-raiser.
'Downgrading our standing'
Mr Perry seized on the fact that the US credit rating was downgraded this month by a leading rating agency following the contentious deal to raise the US debt ceiling this month.
"The fact is for nearly three years president Obama has been downgrading American jobs, he's been downgrading our standing in the world, he's been downgrading our financial stability, he's been downgrading our confidence and downgrading the hope for a better future for our children," Mr Perry said.
He also blasted Mr Obama's foreign policy.
"Our president has insulted our friends and he's encouraged our enemies, thumbing his nose at traditional allies like Israel," he said.
"It's pretty simple. We're going to stand with those who stand with us. And we will vigorously defend our interest. And those who threaten our interest, harm of citizens, we will simply not be scolding you. We will defeat you."
The announcement by Mr Perry, who has made his deep Christian faith a big part of his public image, came one week after he led a seven-hour religious rally in Houston to pray for America, a nation he described as "in crisis."
He put his religious faith on display on Saturday. He asked his audience to remember the US troops killed in Afghanistan last week when their helicopter was shot down by militants.
"Just take a moment to say, 'Thank you Lord that we have those kind of selfless, sacrificial men and women,'" Mr Perry said.
Mr Perry said his state has "the strongest economy in the nation" and that since June 2009 Texas, home to less than 10 per cent of the US population, has been responsible for more than 40 per cent of all of the new jobs created in America.
"He's telling us what we see as the lost promise of America," said Richard Atwater, 67 and retired, who lives in Tupelo, Mississippi, following the speech.
"He's a true conservative," added Paul Holmes of Grand Prairie, Texas.
Mr Perry could draw comparisons to George W Bush, the last Texas governor in the White House, raising the possibility of "Texas fatigue" among voters.
Raised on a west Texas farm, Mr Perry has never lost an election. After a stint in the Air Force, he rose through the ranks of Texas politics from the House of Representatives to agriculture commissioner, lieutenant governor and then governor in 2000 when Mr Bush left for the White House.