Illustration by Tom Bachtell

In the late nineteen-sixties, Mitch McConnell came to Washington to work as an aide to Senator Marlow Cook, a Kentucky Republican. Cook backed clean-air standards and limits on strip mining. It was a time of political diversity among Republicans: in 1970, Senate Republicans endorsed the creation of the Environmental Protection Agency and the Occupational Safety and Health Administration. McConnell was briefly a fellow-traveller of those who regarded government as a source of public protection. He once called the Nixon Administration “at worst, completely reactionary.”

In 1984, McConnell was elected to the Senate, on the coattails of Ronald Reagan’s landslide reëlection. By then, a movement of Southern and evangelical conservatives was rising within the Party. McConnell tacked right periodically, saluting the new Republican leaders. During the Administration of George W. Bush, he backed the President by voting, with Ted Kennedy, to enact No Child Left Behind and the expansion of the Medicare drug benefit. By 2009, after Wall Street melted down, McConnell had risen to Minority Leader, and he forged a deal with Democrats to bail out big banks.

Then the Tea Party rose up in fury, and McConnell moved right again, in an effort to reinvent himself as an anti-government insurgent. It wasn’t easy; he was sixty-nine, and his long jowls and round eyeglasses gave him the look of a Taft Administration clerk. Nonetheless, in 2011, he led the Senate Republicans through a ruthless, extortionate campaign to threaten default on the national debt. It succeeded. President Obama wobbled and accepted budget cuts. Afterward, McConnell called the national debt “a hostage worth ransoming.”

This autumn, he supported the Tea Party radicals’ second threat to default on the debt and a sixteen-day shutdown of the federal government. This time, though, Obama held firm, and, in the end, McConnell and House Speaker John Boehner were forced to choose between Tea Party principles and the viability of the world economy. McConnell negotiated his party’s late-hour capitulation, and, within days, Tea Party groups called for his ouster. The Senate Conservatives Fund, a PAC founded by Jim DeMint, the president of the Heritage Foundation, which has bankrolled Senator Ted Cruz, of Texas, and other highly conservative candidates, announced that it would finance a Republican primary challenge against the Minority Leader next year, because he “has a liberal record and refuses to fight for conservative principles.”

Other veteran Republicans who joined McConnell on the debt-ceiling vote are facing similar challenges from Tea Party-backed candidates. Those targeted include Thad Cochran, of Mississippi, who was elected to the Senate in 1978; Lindsey Graham, of South Carolina; and Lamar Alexander, of Tennessee. In 2012, such primary challenges weakened the Party’s competitive position, and allowed the Democrats to win an eight-seat majority in the Senate. Even now, the insurgents seem less interested in victory than in purification. “We know which senators fought for liberty, and which ones caved to Obama,” Lee Bright, the South Carolina state senator who is challenging Graham, told Slate recently. “We’ve got a list.” The Tea Party’s approval ratings have plummeted since the shutdown ended. Business lobbies and their PACs, appalled by the shutdown’s estimated twenty-four-billion-dollar cost to the economy, are signalling that they may pull back from uncompromising candidates. But the fact that PACs like the Senate Conservatives Fund are willing to force incumbents into expensive, distracting primary fights makes it even less probable that the Republicans can retake control of the Senate.

Like a guerrilla army, the Tea Party is learning how to influence public opinion even when it loses a conventional battle. The budget caps that Obama conceded in 2011 have already enshrined in law a portion of the movement’s draconian fiscal agenda. And although Cruz and his allies in the House won no additional cuts this time, they managed to spread magical thinking among their followers about a possible future debt default. (The next debt-ceiling deadline arrives early next year.) Cruz and the others systematically promoted the idea—the fantasy—that, if the Treasury Department were prohibited from issuing any new debt to finance interest payments and government operations, the country would do just fine. The global economy, this story goes, far from collapsing into crisis, would prove resilient, and, while some nonessential federal departments might wither for lack of funds, that would only demonstrate how Americans could get by with a much smaller government.

This campaign has been dismissed by some Wall Street analysts as just a form of coercive bargaining. Washington is a grand opera of phony crises. Congress has raised the debt ceiling more than seventy times since 1960 without forcing an actual default. It’s tempting to believe that even a diva like Cruz, who, after all, holds a law degree from Harvard and evidently aspires to higher office, would never countenance a final default. Yet history is rife with political radicals who have shocked the world by doing just what they always said they would: Confederate secessionists, for example, who seem to inspire so many Tea Partiers today.

The Tea Party’s anti-intellectualism reflects a longer, deeper decline in the Republican Party’s ability to tolerate a diversity of ideas and public-policy strategies, and to adapt to American multiculturalism. Mitt Romney’s poor showing among Latino voters in 2012 helped insure Barack Obama’s reëlection. Republican leaders, chastened and without any other obvious way to increase their vote base before 2016, pledged earlier this year to revive a comprehensive immigration-reform bill. Yet party leaders, in part because they have been tied down since July by the debt confrontation, haven’t found a way to move legislation past the nativist caucus in the House.

As recently as 2007, when the Bush Administration almost passed a similar bill, it still seemed possible that a modernizing Republican Party might build a formidable political coalition of Latinos, evangelicals, disaffected Catholic Democrats, high-tech entrepreneurs, libertarians, social and educational reformers, and eclectic independents. Instead, as Geoffrey Kabaservice puts it in his history of the Republican decline, “Rule and Ruin,” movement conservatives have “succeeded in silencing, co-opting, repelling, or expelling nearly every competing strain of Republicanism from the party.” Political purges have no logical end point; each newly drawn inner circle of orthodoxy leaves a former respected acolyte suddenly on the outside. That a Tea Party-influenced purification drive now threatens such a loyal opportunist and boardroom favorite as Mitch McConnell seems a marker of the times.

McConnell’s would-be usurper is Matt Bevin, a businessman who owns a bell company; his campaign slogan is “Let Freedom Ring.” He told Glenn Beck recently, “We have got to wean people from this idea of free lunches.” (He might start with fellow Kentuckians; their state pays sixty-six cents in federal taxes for every dollar of federal spending it takes in.) Bevin pleaded, “What we need to tell the American people is that the party’s over.” Presumably, he didn’t mean the Grand Old Party, but the American people may be forgiven for thinking that he did. ♦