Dilma Rousseff, the President of Brazil, and her predecessor, Luiz Inácio Lula da Silva. A scandal engulfing Rousseff’s Presidency has put the future of Brazil’s social compact at risk. Photograph by Igo Estrela / Getty

Richard Nixon was reëlected overwhelmingly in November, 1972, and resigned in August, 1974. Dilma Rousseff, the President of Brazil, looks to be on about the same schedule: reëlected (not overwhelmingly) in October, 2014, and in such deep peril a year and a half later that it seems unlikely that she will finish her term. This week, the largest party in her governing coalition, the Partido do Movimento Democrático Brasileiro, or Democratic Movement Party, voted to leave the government, which is the most severe in what must seem to her a never-ending series of blows.

The obvious cause of Nixon’s downfall was Watergate, and the obvious cause of Rousseff’s is the Lava Jato scandal. In both cases, the name may be mysterious to outsiders. Lava jato means car wash and refers to a penny-ante roadside money-laundering operation in Brasília that, when exposed, provided the first peek at what turned out to be an almost all-encompassing system of corruption. The chief government prosecutor, a youngish judge named Sérgio Moro, from a provincial city in southern Brazil, is now investigating such economic behemoths as Petrobras, the state oil company, and the construction industry, which has been especially busy in the run-up to the 2016 Summer Olympics, in Rio de Janeiro. Every day seems to bring news of another high official under investigation, another corrupt arrangement uncovered, another grant of immunity in exchange for information.

Corruption scandals are a constant feature of Brazilian politics. Government plays a far larger role in the economy than it does in most of the developed world: there are many state-owned businesses, subsidized businesses, and businesses legally protected from competition. And an especially complex and chaotic parliamentary system—at the moment, more than two dozen parties hold seats in the national legislature—means the only way to create a governing coalition is to dole out patronage to parties, often in the form of control over government ministries, in exchange for their support. The reason that Rousseff, a career bureaucrat who had never run for office before, was elected President in 2010 is that the people who were in line for the job ahead of her were felled during a previous scandal. One of her few remaining talking points in her campaign to avoid being impeached is that almost no Brazilian politician can feel entirely safe if Moro’s investigation is permitted to play out indefinitely.

Even by Brazilian standards, though, things seem to have gotten out of hand over the last few years. For example, the prosecutors recently charged João Santana, one of Rousseff’s political consultants and therefore only a second-order political figure, with receiving $7.5 million in funds siphoned from bribes that big companies paid the government in exchange for contracts. There are now almost two dozen separate investigations under way under the broad rubric of the Lava Jato scandal.

It seems unlikely that the driving force in the mega-corruption was personal greed on the part of the rather austere President. Instead, it was probably a combination of the party-time atmosphere produced by the economic boom of the aughts—in particular, high oil prices and the prospect of the Olympics—and Rousseff’s political ineptitude. Lacking the charm and cunning of her predecessor and mentor, Luiz Inácio Lula da Silva, Rousseff seems to have been more reliant on unsubtle means of maintaining a hold on power. In particular, as a far more intellectually consistent leftist than Lula, Rousseff lacks his uncanny instinct for finding a mix of policies that at once reassure economic élites and deliver for an overwhelmingly poor political base. Rousseff’s attempt to bring Lula back into politics as her chief of staff seems to have had two purposes: to immunize him from prosecution, and to enlist him as anti-impeachment lobbyist-in-chief, a role to which he is naturally suited. As of now, a judicial injunction prevents Lula’s appointment from going forward, and that only increases the likelihood of Rousseff’s government collapsing.

The revolt against Rousseff is a middle-class one, in a country that is not yet essentially middle class in the manner of the United States. Like everything that happens in politics, it’s about power and policy, as well as corruption. Brazil’s abrupt shift from prosperity to recession, caused in part by the dramatic fall in oil prices, has made it impossible for investors and politicians to continue to get simultaneous spectacular economic returns. Now they are competitors, and the unlikely consensus over which Lula presided, in which former revolutionaries and bankers appeared to coexist happily within a government ruled by an organization called the Workers’ Party, is gone.

The real losers in the reshaping of Brazilian politics that is to come won’t only be corrupt politicians. The tens of millions of beneficiaries of the generously funded core social programs of the Lula-Rousseff years, Bolsa Família (cash grants to families) and Minha Casa Minha Vida (public housing), are at risk, too. These programs are the heart of the social compact in Brazil, in the way that Social Security and Medicare are here. It will be a tragedy if, in the mad scramble to assemble a new ruling coalition that will almost certainly be more business-friendly, their constituency gets left behind.