President Obama is pursuing a "radical" agenda that is putting the economy and national security in peril, talk show host Rush Limbaugh told "Fox News Sunday," giving the young president failing grades across the board and standing by his sustained criticism of the administration. 

The conservative radio host assailed the administration for its economic stimulus package, health care reform plan and alleged uncertainty over the way forward in Afghanistan. In a wide-ranging interview, he called Obama a "child" driven by his "out-of-this-world ego." 

And he predicted that Obama, who built a broad-based majority over Republican candidate John McCain a year ago, would not win a second term. 

"I'm really, really worried. We've never seen this kind of radical leadership at such a high level of power in the country," Limbaugh said. "I don't think we're better off in any way it could be measured." 

Limbaugh is one of the administration's fiercest critics and has often found himself in the White House crosshairs as a result. Top White House aides blasted Limbaugh earlier in the year for saying he wanted Obama to fail as president. 

Months later, Limbaugh has only doubled down on his criticism. 

"He's immature, he's inexperienced -- in over his head," Limbaugh said of the president. He repeated former Vice President Dick Cheney's charge that Obama is "dithering" on deciding a strategy for the war in Afghanistan. 

And Limbaugh scoffed at the administration's claim that hundreds of thousands of jobs have been saved or created by February's economic stimulus package, saying the government has become the job engine -- not the private sector. 

"I believe that the economy is under siege," he said. 

White House Senior Adviser David Axelrod, reacting to the interview Sunday, downplayed Limbaugh's comments, saying: "We'll let Mr. Limbaugh foment." 

"I think it's a surreal day when you're getting lectures on humility from Rush Limbaugh. ... The fact is that he is an entertainer," Axelrod told CBS' "Face the Nation." "But I think the American people are well-served and believe they're well-served."

Limbaugh also blasted the Democrats' health care bills as a front that would steal money from American businesses and effect the partial takeover of the private sector. 

"This is not about insuring the uninsured -- this is not about health care," Limbaugh said. "This is about stealing one-sixth of the U.S. private sector and putting it under the control of the federal government." 

Limbaugh warned that the legislation currently being worked out in Congress would amount to massive encroachments on personal and private behavior, much of which would fall under the purview of the legislation. 

"And when they get this health care bill -- if they do -- that's the easiest, fastest way for them to be able to regulate every aspect of human behavior, because it will all have some related cost to health care -- what you drive, what you eat, where you live, what you do -- and there will be penalties for violating regulation." 

Limbaugh said these changes would have a drastic effect on the U.S.: "It's going to be the biggest snatch of freedom and liberty that has yet occurred in this country." 

Though he criticized the Republican Party for lacking a clear leader or message that can unify Americans, Limbaugh nevertheless predicted anti-Democratic Party sentiment will propel Republicans to victory in 2010. 

"I know that there is an eruption waiting to happen at the ballot box," he said.