This week, Ralph Nader returned to the political stage with a new book, Unstoppable, whose triumphant subtitle is The Emerging Left-Right Alliance to Dismantle the Corporate State. To kick off his publicity tour, he has argued that liberals should "definitely" impeach President Barack Obama, abandon the "international militarist" Hillary Clinton, and instead embrace Sen. Rand Paul (R-Ky.) as a possible leader of his dream coalition.

To what end? In the book, Nader writes that by marrying the Left with the libertarian Right, we can cut off government support for corporations and have "honest government," "fair taxation," and "more opportunity." Nader sees relatively low-hanging fruit in opposing "sovereignty-shredding global trade agreements, Wall Street bailouts, the overweening expansion of Federal Reserve power, and the serious intrusions of the USA PATRIOT Act against freedom and privacy." He also articulates loftier, if not fully fleshed out, aspirations to "push for environmentalism," "reform health care," and "control more of the commons that we already own."

Some liberal commentators, like Esquire's Charles Pierce and the American Prospect's Scott Lemieux, are dismissing Nader's vision as fantastical, since the Right will never join his progressive crusade. But Nader's vision should not be dismissed so quickly. He leads his book with concrete examples from the 1980s of when he put Left-Right coalitions together to stop an over-budget nuclear reactor project and to pass legislation to protect whistleblowers who uncover wasteful government fraud.

More recently, Sen. Bernie Sanders (I-Vt.), Rep. Alan Grayson (D-Fla.), and then-Rep. Ron Paul (R-Texas) joined forces to pass legislation auditing the Federal Reserve. Nader is correct that there are opportunities to build ideologically diverse coalitions and that coalition building is the key to getting most anything you want out of politics.

However, coalition building requires compromise and, most critically, prioritizing one set of issues over another. The trade-offs inherent in Nader's path into Rand Paul's arms should make liberals run screaming.

The Nader strategy of a permanent coalition with the libertarian Right greatly limits what liberals can accomplish. Where there is a joint desire to restrain government (end the drug war) and limit spending (stop corporate welfare), a Nader-Paul alliance can form. But you can forget about anything that involves new government regulation, higher taxes, and more spending. That would preclude big-ticket liberal priorities like capping carbon emissions, expanding anti-poverty programs, guaranteeing universal preschool, and investing in infrastructure.

Nader effectively deprioritizes those goals, because his primary agenda is to "Dismantle the Corporate State." But the hard truth is that if liberals want to make progress on their core agenda, the coalition to nurture is not with the Paulistas. It's with the CEOs.

The little-talked-about secret of most major liberal accomplishments over the past 80 years is that they received some degree of corporate support, at least enough to disempower conservative opposition. This is true for much of FDR's New Deal, LBJ's anti-poverty legislation, and environmental regulation, as well as Obama's stimulus, repeal of the Bush tax cuts, Wall Street regulation, and health-care reform.

As I observed in the New York Times following the Supreme Court's upholding of ObamaCare, "When corporations are divided or mollified, reformers can breathe. The president can be heard. Business owners can be convinced that they will remain profitable. The dim prospect of perpetual gridlock can be trumped by the allure of regulatory certainty."

Nader wants to scrap this long, if quiet, history of liberal success that has built the pillars of modern activist government in favor of prioritizing a civil libertarian agenda. His strategy makes sense if you think smashing the NSA is more important than saving the climate or feeding the hungry. I suspect most liberals would not make that trade.

There's nothing wrong with forging temporary, limited partnerships with whoever is willing to play ball at that moment. You can work with libertarians against corporations on global trade today, and cooperate with corporations against libertarians on funding infrastructure tomorrow.

But Nader's vision goes beyond ad-hoc coalitions. He wants to permanently side with government-hating libertarians over government-accepting corporations. That may have superficial appeal to liberals currently agitated over income inequality, but it's not the strategy that helped liberals in the past century build the social safety net, reduce poverty, and avoid another Great Depression.