In 2010, Lindsey Graham could see it coming.

"You know what I worry most about?" the Republican Senator from South Carolina told CNN about the growing opposition to the war in Afghanistan. "An unholy alliance between the right and the left." If the war continued to yield no clear victories for the U.S., libertarian-leaning Republicans who believed it was "impossible for us to win" could join with "people on the left who are mad with the president because he is doing exactly what Bush did and we're in a war we can't win." Such a coalition would pose the gravest threat to the joint war-making project of the Republican and Democratic establishments. "My concern is that, for different reasons, they join forces and we lose the ability to hold this thing together."

Six months later, progressive icon Ralph Nader saw the potential power of a libertarian-left alliance, too, but welcomed it. Appearing with Ron Paul on Judge Andrew Napolitano's "Freedom Watch" show on Fox Business Network in January 2011, Nader issued a manifesto for "a dynamic political force" that would not only stop the war in Afghanistan but radically re-shape American politics. What he called "genuine libertarian conservatives" were "great allies" and together with "many liberals and progressives" could challenge "the bloated, wasteful military budget," "undeclared wars overseas," "hundreds of billions of dollars of corporate welfare," "invasions of our civil liberties and civil rights," "the sovereignty-shredding, job-destroying NAFTA and World Trade Organization agreements," and the "completely out-of-control" and unaccountable Federal Reserve System. Nader could also have mentioned the criminalization of drugs, police abuses, and immigration restrictions, which the left and libertarians have fought together against for years.

In fact, Graham's fears and Nader's hopes have now been realized. Never has there been a greater convergence of libertarian and leftist activities, never has it given more trouble to the powers of Washington, D.C., and never has it been a greater cause of concern, hope, and conflict among the political intelligentsia.

Eight months after Nader's "Freedom Watch" pronouncement, Ron Paul supporters along with socialists, anti-market anarchists, and other lefties of various stripes were the first to set up camp in Zuccotti Park and launch the Occupy Wall Street movement. There were arguments over whether advocates of free markets belonged in the movement, whether the economic crisis was caused by deregulation or by government encouragement of high-risk financial speculation, and whether the solution to the crisis was greater or less government control of business, but the libertarians stayed. As Occupy spread to other cities, libertarians were almost always a visible—though minority—presence at the encampments. "One would more reliably come across vocal Ron Paul supporters at Occupy events than vocal Obama supporters," reported Michael Tracey in the American Conservative. "It was not lost on the Zuccotti Park crowd, for instance, that Ron Paul personally expressed a measure of support for the movement earlier than most any other national U.S. politician–aside from Sen. Bernie Sanders or Rep. Dennis Kucinich."

Occupy is often derided as having been leaderless and ineffective, but in conjunction with the Tea Party, few if any social movements in American history have done more to identify and discredit collusion between government and corporations. "Corporatism," once a term confined to academic discourse, is now routinely used to describe the general relationship between government and business in the United States. Moreover, it seems safe to assume that because of the efforts of Occupy and the Tea Party, which began in 2009 largely as a protest against the Troubled Assets Relief Program, few if any members of Congress will vote for another massive corporate bailout in the foreseeable future without fear of upsetting their constituents.

Since the start of 2013, the "dynamic political force" has proved itself to be just that. Obama's second inaugural address was greeted with tepid approval and grumblings of discontent from his formerly orgiastic supporters, who were likely more chastened by four years of relentless exposures and criticisms of their hero's policies by leftists and libertarians than by the policies themselves. In March, pundits who otherwise consider Rand Paul to be an exotic white supremacist cheered the Kentucky Senator as he filibustered the nomination of John Brennan as director of the CIA in protest of the administration's use of drones to kill U.S. citizens suspected of terrorism. At Salon, David Sirota called Paul's stand "heroic" while Jon Stewart celebrated him for "using the filibuster the way it's meant to be used." Straight-up communist columnist Ted Rall went further, declaring that Paul had become "the most, perhaps the only, establishment political figure expressing a progressive vision on a host of incredibly important issues… issues that have been abandoned by the state-sanctioned Left."

At the libertarian International Students for Liberty Conference in February of this year, Jeremy Scahill, whose associations include the International Socialist Organization, Democracy Now!, and The Nation even though he has consistently allied himself with libertarians on national security and foreign policy issues, forthrightly declared that Rand Paul was "reflecting what should be some of the core values of liberals, when it comes to questions of civil liberties, of the rights of Americans to know whether they're on a kill list, on the right of the Congress to know what assertions the White House is making about who it can assassinate around the world, how it determines the guilt of individuals that it wants to target for drone strikes." Scahill acidly noted that "not a single Democrat" would join with Paul in his protest.

Though various polls show that roughly two-thirds of Americans support Obama's use of drones against suspected terrorists in foreign lands, that number would almost certainly be greater were it not for the continued protests against the drone program by an amalgamation of libertarian-leaning Republican politicians, such as the recently-retired Ron Paul and his son Rand, Rep. Justin Amash of Michigan, and Rep. Walter Jones of North Carolina, anti-interventionist libertarian intellectuals and pundits, and public figures such as Scahill and Glenn Greenwald who are to the left of the Democratic Party establishment. This is the group that publicized the executive-ordered killings of U.S. citizens Anwar al-Awlaki and his 16-year-old son Abdulrahman, gave force to Rand Paul's filibuster protest, and turned public opinion against one of the administration's most significant, autocratic, unconstitutional, and dangerous foreign policy initiatives. Following Paul's day on the Senate floor, Gallup reported a majority of Americans opposing drone strikes against U.S. citizens, even against those on foreign soil suspected of terrorism.

In the summer of 2013 the "unholy alliance" wreaked havoc on the national-security and foreign-policy establishments. Edward Snowden, a Ron Paul supporter, received passionate support from both libertarians and a broad array of leftists for revealing, at the risk of imprisonment, the NSA's dragnet surveillance of American citizens. Snowden's disclosures were publicized by the journalist Glenn Greenwald, who is a regular speaker at the International Socialist Organization's annual Socialism Conference, a recipient of the Nation Institute's I.F. Stone Award, and according to Rachel Maddow "the American left's most fearless political commentator." But Greenwald is also, like Scahill, an eager collaborator with libertarians. He authored a study for the Cato Institute on Portugal's decriminalization of drugs and frequently praised Ron Paul for being "far and away the most anti-war, anti-Surveillance-State, anti-crony-capitalism, and anti-drug-war presidential candidate in either party."

According to USA Today/Pew Research Center polls, attitudes toward "the government's collection of telephone and internet data as part of anti-terrorism efforts" turned decidedly negative after Snowden and Greenwald began their exposé. In June 2013, when the public first heard of the NSA's program, 48 percent of those polled approved of it while 47 percent disapproved. By January 2014, approval declined to 40 percent and disapproval rose to 53 percent. That disapproval turned to rage that spilled into the streets and across the World Wide Web on "The Day We Fight Back," a global protest in February when more than 6,000 websites and tens of thousands of flesh-and-blood protestors in 15 countries demanded "new laws that curtail online surveillance." Supporters of the protest included the astonishing combination of FreedomWorks, Ron Paul's Campaign For Liberty, the Libertarian Party, Greenpeace, and Green parties across the world.

Less than two months after Snowden and Greenwald took on the surveillance state, the Obama administration received yet another setback from the unholy alliance. While liberal and neoconservative pundits cheered the President's announcement on August 31 that "the United States should take military action against Syrian regime targets" and his submission of a draft resolution to Congress seeking authorization for an attack, an unprecedented vanguard of limited-government, anti-government, and workers-government activists led thousands of people into the streets to stop the intervention. At demonstrations across the country, Ron Paul signs and Gadsden flags shared sidewalk space with banners of the Party For Socialism and Liberation. Even The New York Times noted "some unusual newcomers" at anti-war rallies—Tea Partiers mobilized by their local organizations and by FreedomWorks, which organized a phone bank of its members to lobby members of Congress to oppose intervention in Syria. Meanwhile, in the Congress members of the Republican Liberty Caucus joined with the independent socialist Senator Bernie Sanders of Vermont and left-of-center Democrats to argue against Obama's resolution. That resistance compelled the White House to abandon its plans to send Tomahawk missiles into Syria and seek an agreement with Syria's Assad regime to destroy its chemical weapons cache. Widely derided by Republican hawks as "a failure," Obama's decision to forego lethal action should certainly be counted a great success for the antiwar left and libertarians.

In addition to these impressive achievements we have seen long-standing collaboration of the left and libertarians bring two revolutions to the consciousness of Americans. The movement to decriminalize drugs, which since the early 1970s has been led by left-libertarian organizations like the National Organization for the Reform of Marijuana Laws (NORML) and the Drug Policy Alliance—an organization that receives funding from both George Soros and the Koch brothers—not only succeeded with the passage in 2012 of initiatives in Colorado and Washington legalizing recreational use of marijuana but also with a sea-change in American attitudes. In October of last year, Gallup reported that for the first time a clear majority of Americans—58 percent in their latest poll—said the drug should be legalized. When Gallup first asked the question in 1969, the year before NORML was founded, only 12 percent favored legalization.

Most recently, libertarians, progressives, and even many establishment liberals flooded social media and the airwaves in response to the police killing of the unarmed black teenager Michael Brown in Ferguson, Missouri and to the subsequent use of tanks, snipers, and tear gas by the St. Louis County Police to counter protesters. The phrase "militarization of the police," first popularized by the work of former Reason senior editor Radley Balko, is now coursing through American political discourse. Noting that Rand Paul and the Congressional Black Caucus were leading the push on Capitol Hill for police reform in response to Ferguson, the liberal Washington Post blogger Greg Sargent welcomed this "left-right alliance" for focusing "national attention on the over-militarization of our police forces."

One might think all this would be cause for celebration among those who share Nader's objectives, but many find it more a cause for grave concern. Since last summer, liberal media outlets have streamed out warnings to their readers to "Beware of Libertarians Bearing Gifts," as the Center for American Progress put it. Any alliance with libertarians, even for a cause as worthy as reining in the NSA, "could kill the New Deal." Salon has frequently trafficked in hysteria over the libertarian "threat" to progressivism. "Don't Ally With Libertarians," admonished one of many headlines about the "fatally compromised" coalition that produced "The Day We Fight Back." At The New Republic, Princeton history professor Sean Wilentz explained to the "liberal establishment" that had fallen in with Snowden, Greenwald, and Wikileaks founder Julian Assange that these purveyors of "paranoid libertarianism" were outside the bounds of respectable politics. They occupy "a peculiar corner of the political forest, where the far left meets the far right, often but not always under the rubric of libertarianism." Where unwitting liberals have "portrayed the leakers as truth-telling comrades intent on protecting the state and the Constitution from authoritarian malefactors, that's hardly their goal," Wilentz warned. "In fact, the leakers despise the modern liberal state, and they want to wound it."

Some left-wing observers have offered more constructive evaluations of the alliance. Ralph Nader continues to lead the way, with a new book on the "Emerging Left-Right Alliance to Dismantle the Corporate State" and a lengthy interview promoting it on Reason TV. Perhaps the most notable among the left-wing sympathizers to Nader's cause is Peter Frase, an editor at the socialist Jacobin, who questioned "this obsession with people like Greenwald and Snowden as vectors for noxious libertarianism rather than people who are doing courageous and useful work even if their politics aren't socialist." Frase identified "an instinct among some on the Left to suppose that defending the possibility of government requires rejecting any alliance with libertarians who might criticize particularly noxious aspects of the existing state." For those on the left who share Nader's optimism about libertarians, Frase's conclusion should serve as a manifesto:

One should not have any illusions that critics of the national security state all share socialist politics. But we should judge these critics by what they say and do and what their political impact is. An endless inquisition into hidden beliefs and motives, and the attempt to unmask a devious libertarian hidden agenda, makes for a satisfying purity politics for those who want to justify their own inaction. But it does nothing to contest the predatory fusion of state and capital that confronts us today, which must be confronted in the government, the workplace, and many other places besides.

Hear, hear. So let us say to leftists and libertarians: Unite! You have nothing to lose but your ideological chains.