NORTH CHARLESTON, South Carolina George W. Bush returned to the campaign trail on Monday for the first time since he left the White House, mounting a defense of his legacy and his brother Jeb's campaign after both were targeted by Donald Trump during the South Carolina Republican debate last weekend.

The former President issued a series of thinly-veiled attacks on Trump and touted his brother as a "steady hand" in a time of emerging national security threats.

"I understand that Americans are angry and frustrated but we do not need someone in the Oval Office who mirrors and inflames our frustration," George W. Bush told a crowd of 3,000 gathered in North Charleston. "We need someone who can fix the problems that cause our anger and frusturation, and that's Jeb Bush."

George W. Bush never mentioned the Republican frontrunner's name, but the contrast he drew between "his big little brother" and Trump was obvious as he defined "real strength" coming from "integrity and character."

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"Strength is not empty rhetoric, it is not bluster," George W. Bush said, flanked on stage by former First Lady Laura Bush and South Carolina Sen. Lindsey Graham, who has endorsed Jeb's campaign. "And in my experience, the strongest person usually isn't the loudest one in the room.

Jeb Bush spoke directly after his brother, ditching his signature eyeglasses and delivering one of the more impassioned speeches of his campaign -- embracing his brother's record in the same words he used during the GOP debate Saturday.

"While Donald Trump was building a reality TV show, my brother was building a security apparatus to keep us safe and I'm proud of what he did," he said.

Bush called it "weird" for Trump to discuss "impeaching a Republican two-term president who is extraordinarily popular for good reason among Republicans" on the debate stage.

"Some of the dialogue back and forth made me wonder - if closed my eyes, I thought it was Michael Moore on the stage," Jeb joked.

But Bush said the campaign was bigger than Trump.

"I can beat Hillary Clinton. I can promise you that," he told a roaring crowd, which appeared as equally enamored with him as they were with his brother. "The only way we win is to do what Republicans, when they win, always do. Campaign like George W. did. Campaign like Ronald Reagan did."

The younger Bush has been reluctant for most of the race to publicly draw on his brother's support, but he finally decided to put his brother to work in South Carolina, with its heavy population of veterans and multiple military bases.

It remains to be seen whether this gambit will pay off. While it's true the former president is personally popular in the state and won a competitive primary in South Carolina, that was sixteen years ago.

The crowd here, though, only wished that he had come out onto the trail sooner.

"Bringing in his brother would have brought more spotlight to him than he got," Aaron Holley, an undecided Republican voter from Charleston, told CBS News. "I think bringing in George was a good idea. And I think he should have done it earlier."

George W. Bush privately met with South Carolina Governor Nikki Haley prior to his appearance in Columbia, South Carolina. He praised the nation's first Indian-American woman to become Governor. Haley's endorsement is highly coveted -- especially by the campaigns of Bush and Marco Rubio.

"Thank goodness our country welcomed her parents from India when they immigrated here in 1969," George W. Bush said of Haley.