Presumptive Republican presidential nominee and former Massachusetts Gov. Mitt Romney announced Aug. 10 that he had selected Wisconsin U.S. Rep. Paul Ryan as his running mate. Ryan, 42, was first elected to the House in 1998, at the age of 28, and has been there ever since, where he currently serves as chairman of the Budget Committee.

Most Americans had never heard of Ryan before the VP announcement according to a series of polls done by YouGov for the Cooperative Campaign Analysis Project. To the extent people do know him it tends to be for his congressional budget blueprint, widely known as the Ryan Plan or the Ryan Budget, which would, among other things, turn the extremely popular Medicare program, which now guarantees coverage for seniors, into a voucher system.

Ryan, who consistently comes off as polished and reasonable, is a veritable rock star among tea partiers and others on the right. But many on the left regard him as a dangerous radical who wants to undo the New Deal and fundamentally alter the social contract that has evolved in this country beginning with President Franklin Roosevelt’s New Deal.

Ryan is a lifelong devotee of Russian émigré writer and philosopher Ayn Rand, author of such works as Atlas Shrugged and The Fountainhead. Rand, a self-avowed atheist, espoused a philosophy she called Objectivism. She published a series of essays entitled The Virtue of Selfishness and believed, according to a 1989 biography by Leonard Peikoff, The Voice of Reason, that the individual should “exist for his own sake, neither sacrificing himself to others nor sacrificing others to him.”

In a now-legendary 1959 interview with Mike Wallace, Wallace put this to Rand: “You are out to destroy almost every edifice of the contemporary American way of life, our Judeo-Christian religion, our modified government regulated capitalism, our rule by majority will. Other reviews have said you scorn churches and the concept of God. Are these accurate criticisms?” Rand responded simply, “Yes.”

In the same interview, Rand labeled “the kind of altruism by which we live” as “evil.”

“I grew up reading Ayn Rand and it taught me quite a bit about who I am and what my value systems are, what my beliefs are,” Ryan said in a 2005 speech to The Atlas Society, a group that promotes Rand’s philosophy. “It’s inspired me so much that it’s required reading in my office for all my interns and staff.”

“There is no better place to find the moral case for capitalism and individualism than through Ayn Rand’s writings and works,” Ryan declared in the same speech.

By April of this year, however, Ryan was singing a decidedly different tune. Responding to a piece by Nobel laureate Paul Krugman pointing out Ryan’s devotion to Rand, Ryan was quoted in the conservative National Review as saying of her, “I reject her philosophy. It’s an atheist philosophy. It reduces human interactions down to mere contracts and is antithetical to my worldview.”

Earlier this year, the Republican-dominated U.S. House passed a version of the Ryan Budget he called “The Path to Prosperity: Restoring America’s Promise.” Only four Republican representatives voted against it. The bill died in the Senate, which is controlled by the Democrats, with only five Republican “no” votes.

The Ryan Budget’s most controversial feature is that it would turn Medicare into a voucher system for anyone younger than 55, the New York Times reports. The federal government would provide each senior with a fixed payment, in essence a voucher, which he or she would then use to shop for a private policy, or to help pay for traditional Medicare. The growth in Medicare spending, however, would be capped at no more than the growth of the overall economy, plus one half of one percent. But because health care costs have historically and reliably increased at greater rates than the general economy, the nonpartisan Congressional Budget Office has said that, under Ryan’s plan, “most elderly people would pay more for their health care,” averaging roughly an additional $6,400 yearly in 2022.

Ryan also has big plans for Medicaid, the federal program that provides health care to the poor. He would cut that program by over $770 billion, according to the website of Sen. Bernie Sanders, I-Vt., a member of the Senate Budget Committee, and would turn the system into block grants to the states, with states enjoying enhanced discretion as to how to spend the money.

The Ryan Budget would also slash funding for Pell Grants for college students by 60 percent, reducing the maximum grant from $5,500 to $2,100, Sanders says. Funding for infrastructure would be cut by 40 percent in the first year alone.

At the same time, Ryan’s plan would increase defense spending, make the Bush tax cuts permanent for all income levels and, in fact, provide additional tax cuts that would skew towards wealthier taxpayers.

Ryan’s plan calls for offsetting the revenue loss his tax cuts would generate in part by closing tax loopholes and eliminating certain deductions, but he provides no detail at all as to which loopholes and deductions would be targeted.

Republicans applaud Ryan and his budget plan as a courageous, serious attempt to rein in what they view as out-of-control government spending. Democrats and those on the left argue that Ryan’s numbers don’t add up and that his budget is little more than a means of working a massive redistribution of wealth from the have-nots to the haves and fundamentally reordering the relationship of American citizens and their government. Paul Krugman dubbed Ryan the “Flimflam Man,” and argued that the Ryan Budget would explode the deficit in an Aug. 5, 2010, New York Times piece.

Ryan’s credibility as a deficit hawk is somewhat tarnished by his voting record during the latest Bush presidency. Ryan voted for both Bush tax cuts, 2001 and 2003, for the unfunded Medicare prescription drug plan, for authorization of the Iraq war, for the Troubled Asset Relief Program (a major Republican bugaboo) and for the massive 2008 bank bailout.

Ryan was a vocal critic of President Obama’s 2009 stimulus program but, according to the Boston Globe, this did not prevent him from writing at least four letters to the Secretary of Energy seeking millions in stimulus funds for Wisconsin conservation groups.

Ryan is also on the far right wing of his party on social issues. With respect to LGBT concerns, he was indeed one of only 35 Republicans to vote in favor of the failed Employment Non-Discrimination Act in 2007, equalitygiving.org reports. (His position on extending ENDA’s protections to transgenders is unknown. Romney opposes ENDA at the federal level.)

But he voted against the Matthew Shepard and James Byrd Jr. Hate Crimes Prevention Act passed with bipartisan support and signed into law by President Obama in 2009.

Ryan also voted against repeal of the military’s “Don’t Ask, Don’t Tell” policy, which was repealed in 2010 with the repeal implemented last year.

Ryan strongly opposes marriage equality. He spoke out in support of a Wisconsin constitutional amendment that even forbids civil unions that are too close to being marriages.

He also voted in favor of prohibiting gay adoptions in the District of Columbia in 1999.

The Human Rights Campaign gave Ryan a voting record score of zero, out of a possible 100, in each of the five Congresses preceding the current one, except 2007, when he received a 10 for his ENDA vote, according to Daily Kos.

Despite all this, the Log Cabin Republicans, a gay GOP group, lauded Ryan’s elevation to the ticket. “Congressman Paul Ryan is a strong choice for vice president, and his addition to the GOP ticket will help Republican candidates up and down the ballot,” Executive Director R. Clarke Cooper said.

Ryan also faces some headwinds on women’s issues. In the current Congress, he co-sponsored a so-called “personhood” bill that would give all the rights of citizenship to fertilized eggs, the Huffington Post reports. Even voters in socially conservative Mississippi rejected a ballot initiative to the same effect by double digits. Ryan also voted to defund family planning programs and against the Lily Ledbetter Fair Pay Act of 2009, which became law and which expands women’s rights to sue for pay discrimination.

“The Romney-Ryan ticket is dangerous to women’s health,” said Nancy Keenan, president of NARAL Pro-Choice America.

The Ryan nod has been greeted with great enthusiasm, at least publicly, on both sides of the political spectrum. “Paul Ryan is the one VP pick who can unite liberal and conservative America. #CouponsCouponsCoupons,” MSNBC’s Rachel Maddow tweeted.

Democrats and the Obama campaign appear to be genuinely thrilled by the choice. Obama has plainly been planning to do everything in his power to link Romney to the unpopular Medicare provisions of the Ryan Budget. (A 2011 CNN/Opinion Research Corporation poll revealed that 58 percent of Americans opposed Ryan’s plans for Medicare, with 74 percent of seniors opposed.) Obama spokespersons and surrogates have been referring to the “Romney-Ryan Plan” for months. Romney has now made the linkage explicit by making Ryan his running mate, and the GOP ticket will without doubt be pounded with the charge of wanting to “end Medicare as we know it” all the way to the election. Democrats also see the Ryan choice as proof that Romney realized his chances had dimmed over the summer and that he was attempting, if not quite a full-blown hail Mary pass, something close. They are also pleased that Romney appears to have conceded that the election will be about a choice between competing visions for the country’s future, as the Obama campaign has wanted all along, instead of a referendum on Obama’s handling of the economy.

Despite increasing right-wing pressure over the preceding couple of weeks to pick Ryan, many had expected Romney to instead opt for a “boring white guy,” such as former Minnesota Gov. Tim Pawlenty or Ohio Sen. Rob Portman. Commentary on the right about Ryan has been largely positive, with most pundits and politicians lauding Romney for making a “bold,” potentially “game-changing” choice.

“Change is now on the side of the Republicans,” Charles Krauthammer said on the Fox News channel. Pawlenty and Portman also praised the Ryan pick.

But it appears that there are serious behind-the-scenes doubts within the GOP, according to an Aug. 14 post by Alexander Burns, Maggie Haberman and Jonathan Martin at Politico.

“Away from the cameras, and with all the usual assurances that people aren’t being quoted by name,” Burns, Haberman and Martin write, “there is an unmistakable consensus among Republican operatives in Washington: Romney has taken a risk with Ryan that has only a modest chance of going right—and a huge chance of going horribly wrong.”

GOP insiders express concern that the Medicare issue might sink Romney in Florida, with its huge population of seniors, and in other states with graying populations. Most analysts believe Romney cannot win without taking the Sunshine State.

There are also fears that making Medicare a central campaign theme could cost Republicans seats in Congress if representatives’ and senators’ pro-Ryan Budget votes come back to haunt them.

However it plays out, one thing seems certain—the 2012 race just got a whole lot more interesting.