Mitt Romney, who will be officially nominated this week as the Republican nominee for president, appears to trim his social convictions to the party’s prevailing winds. There is no doubt, however, about where the party’s vice-presidential candidate stands. A long history of social extremism makes Paul Ryan an emblem of the Republican tack to the far right.


Mr. Romney’s choice of Mr. Ryan carried some risks, considering Mr. Ryan’s advocacy of overhauling Medicare, but it has sent the strongest signal of solidarity to those who have made the party unrecognizable to moderates. Strident conservatives had been uneasy with Mr. Romney, but it is the rest of the country that should be nervous about conservatives’ now-enthusiastic acceptance of the Republican ticket.


Mr. Ryan is best known as the face of Republican budget-cutting, though his ideology runs much deeper. For years, he has been a reliable vote against workplace equity for women, opposing the Lilly Ledbetter Fair Pay Act, which makes it easier for women to file wage-discrimination lawsuits, and two similar measures.


The full outpouring of hard-right enthusiasm is based, to a large degree, on Mr. Ryan’s sweeping opposition to abortion rights. He has long wanted to ban access to abortion even in the case of rape, the ideology espoused in this year’s Republican platform. (Mr. Romney favors a rape exception.) Mr. Ryan also co-sponsored, along with Representative Todd Akin of Missouri, a bill that would have narrowed the definition of rape to reduce the number of poor women who can get an abortion through Medicaid.


Besides that, he has co-sponsored more than three dozen anti-abortion bills, including measures that would require women to get an ultrasound first, bar abortions after 20 weeks in the District of Columbia and end federal spending for family planning programs. Though he urged Mr. Akin to end his Senate race last week over an offensive remark about “legitimate rape,” Mr. Ryan has actually co-sponsored more of these measures than Mr. Akin.


“I’m as pro-life as a person gets,” he said in 2010.


He also co-sponsored a bill last year to allow employers to decline coverage of birth control if it violated their moral or religious convictions, and his budget would end all government financing for Planned Parenthood while slashing spending on prenatal care and infant nutrition. Mr. Ryan’s record on gay rights is no less egregious. He supports a constitutional amendment to ban same-sex marriage, and voted against the repeal of the military’s discriminatory don’t-ask, don’t-tell policy. In 2009, a decade after Matthew Shepard was murdered for being gay, Mr. Ryan voted against a bill named after Mr. Shepard that expands the federal hate crimes act to include brutality based on sexual orientation.


In 1999, he even voted to prevent same-sex couples in the District of Columbia from adopting children. In a break with his party, however, he supported a 2007 bill outlawing job discrimination based on sexual orientation.


Mr. Ryan is one of the most anti-gun-control candidates on a presidential ticket in many years, holding a grade of “A” from the National Rifle Association and opposing a background check requirement for purchases at gun shows.


The crowd at the Republican National Convention this week will faithfully support Mr. Romney’s nomination, but its heart will be closest to the younger man with the more radical ideas standing at his side.