NORTH CHARLESTON: Former president George W Bush, campaigning for his brother for the first time, told a raucous crowd on Monday that Jeb had the temperament and backbone to be commander in chief.

He also not-so-subtly ripped into Republican presidential frontrunner Donald Trump, warning American voters that the best applicant for the world’s most powerful job was not necessarily the loudest, but the one who could best apply his skills and learning to the position.

“I’ve seen Jeb in action. He’ll be a strong and steady hand when confronted with the unexpected,” Bush said of his brother, who is seeking a boost to his fortunes in South Carolina, which on Saturday becomes the third state to vote in the presidential nominating contest leading up to the November election.

Trump’s controversial remarks and policy positions — last year he called for a ban on Muslims entering the United States — have caused an uproar.

But he is an anti-establishment outsider seizing on voter anger and frustration with Washington, and remains firmly at the top of the polls even after turning American political convention on its head.

George W’s message: don’t buy into it.

“I understand that Americans are angry and frustrated, but we don’t need someone in the Oval Office who mirrors our anger and frustration,” Bush told one of Jeb’s largest crowds since the former Florida governor launched his presidential bid last June.

“There seems to be a lot of name calling going on, but I want to remind you what our good dad told me one time,” Bush said of their father, the former president George HW Bush.

“Labels are for soup cans. The presidency is a serious job that requires sound judgment and good ideas,” he added, stressing that his brother is the Republican candidate “who can win in November.”

It was a polished speech, filled with Dubya’s trademark Texas twang, by a controversial politician whose dynastic family remains steadfastly popular in South Carolina.

With the elder Bush brother launching into the caustic Republican nomination fray, Trump unleashed a new round of invective at his challengers.

The political rhetoric in the presidential race has sharpened dramatically since the Iowa caucuses and the New Hampshire primaries earlier this month.

Trump rounded on the former president during Saturday’s debate in a bid to blunt any Bush progress, and he continued the assault Monday at a press conference, slamming George W, who was president during the 9/11, 2001 terror attacks.

“So you had that. You obviously had the war which was a big mistake. I think few people would say the war in Iraq was a positive,” Trump said.

Jeb Bush, for his part, argued that Americans should want an experienced hand at the tiller, especially when it came to national security.

“Who is going to be the steady hand to keep us safe?” he said.

Trump also scolded Senator Ted Cruz, his current closest competitor, as “totally unstable” and a “liar” for attacking Trump’s earlier, liberal positions on abortion and health care.

And he repeated his threat to sue Cruz over his eligibility to be president, with Trump insisting that Cruz, who was born in Canada, is not a natural born citizen as the US Constitution requires candidates to be.

At an event in Mount Pleasant, the brash billionaire also lashed out at the party itself, calling the Republican National Committee a “disgrace” after he was loudly booed at Saturday’s Republican debate by an audience that Trump said was stacked with establishment lobbyists.

“The whole room was made up of special interests and donors, which is a disgrace from the RNC,” Trump said. “The RNC better get its act together.”

Trump leads by a stunning 20 points over Cruz in the Palmetto State, known for its brutal political atmosphere.

Senator Marco Rubio, who is seeking a resurrection after fizzling in New Hampshire and finishing fifth there, is third at 14.3 percent, followed by a 10.5-percent showing for Ohio Governor John Kasich, whose impressive second place New Hampshire finish was helping him surge here.

Bush is fifth at 10 percent, with former neurosurgeon Ben Carson pulling up the rear in South Carolina with 4.5 percent.

Adding to the campaign intensity, and perhaps tearing at the very fabric of the Republican Party, candidates were digesting the implications of the political thunderclap brought by the sudden death of conservative Supreme Court justice Antonio Scalia.

His death Saturday has set off an epic election-year battle over his successor that will shape American life far into the future.

Meanwhile, Kasich has positioned himself as the man above the fray, presenting a heartening, optimistic message to voters and urging them not get sucked into the Republican-on-Republican vitriol that he says only increases the chances of a Clinton victory in November.

(AFP)