The world’s largest nonnuclear power and fourth-largest democracy is in the midst of a political crisis it can’t seem to escape. Over the past three years, Brazil’s ever-growing corruption scandal has enveloped hundreds of politicians. President Dilma Rousseff was impeached last fall. And last Wednesday, Brazil’s problems got even worse: A federal judge convicted the country’s former president, Luiz Inácio Lula da Silva, on charges of corruption and money laundering. The conviction and potential imprisonment of a former president, especially one who was a leading candidate for next year’s presidential election, will throw Brazil even deeper into crisis. But it should also cause concern for the rest of the world. Without a stable Brazil, it will be hard — perhaps impossible — to solve the planet’s most pressing international problems. “The world needs Brazil,” said Mark Langevin, the head of the Brazil Institute at George Washington University’s Elliott School of International Affairs. The country’s largest natural resource, the Amazon rainforest, is crucial in the global fight against climate change, and the debate over how to protect it continues to rage in Brazil. Brazilian President Michel Temer is currently pushing legislation that would remove protections from an area of the Amazon the size of Portugal. And after years of substantial progress cutting greenhouse gas emissions during Silva’s time in office, such emissions have increased in recent years. Brazil is also on track to become the largest exporter of food and agricultural products over the next decade. It is home to nearly one-fifth of the world’s available freshwater and is among the leading producers of sustainable biofuels, meaning the country is positioned to help address potential effects of climate change — including food and water scarcity in certain parts of the world. Brazil’s strong relations with China and improving relations with other world powers — including the U.S., Russia and the European Union — also allow it to engage in “a great balancing act” between nations with more adversarial relationships, Langevin said. “You cannot have a serious discussion on climate change, on sustainability, on food security, if Brazil is not at the table,” said Paulo Sotero, the head of the Brazil Institute at the Woodrow Wilson International Center for Scholars, a Washington-based think tank. But, he added, “the Brazil that has to be at the table is a credible Brazil, a Brazil that is managing itself and its economy in a proper way.”

MIGUEL SCHINCARIOL/AFP/Getty Images Luiz Inácio Lula da Silva, once "the most popular politician in the world," was convicted on corruption charges last week but still plans to seek the presidency in 2018.

Therein lies the problem. Right now, Brazil’s seat at the table often seems unoccupied. The corruption scandal is a big reason for that. Da Silva ― popularly known as “Lula” ― is not the first, nor will he be the last, politician to succumb to Operation Car Wash, the expansive corruption probe that began as a simple money laundering investigation in 2014 but has since grown into the world’s broadest political scandal. Temer, Brazil’s current president, is also facing allegations of corruption and bribery that could spark impeachment proceedings in Congress, and his critics have alleged that his support for the Amazonian deforestation bill is a horse-trading maneuver meant to win the backing of influential actors in the battle to save his job. Brazil’s struggles in addressing climate change, some observers have asserted, even kept Temer from effectively criticizing U.S. President Donald Trump for pulling the United States out of the Paris climate agreement. Those same allegations of bribery nearly caused Temer to skip this month’s G-20 summit in Hamburg, Germany. Once Temer finally decided to attend, he was largely an afterthought: He didn’t conduct a single closed-door meeting with another head of state (Finance Minister Henrique Meirelles went to two in his place), and, perhaps due to his waffling on even attending the conference, Temer saw his name omitted from the press program that listed other foreign leaders. When he did speak, he insisted that Brazil wasn’t actually facing an economic crisis. To many Brazilians, da Silva has seemed like the solution to the country’s many problems. He was perhaps the most transformational elected official in Brazilian history: a former labor leader with little formal education who became Brazil’s first working-class president. A member of the leftist Workers’ Party, da Silva enacted social and economic policies that helped distribute the nation’s rapid economic gains to people with underprivileged backgrounds similar to his own. Da Silva’s Brazil lifted some 30 million people out of poverty. His expansive social welfare policies helped lead to Brazil’s removal from the United Nations world hunger map. Brazil experienced vast advances in literacy, education and public health, while da Silva’s affirmative action policies for government hiring brought black Brazilians and women into positions of power they’d rarely, if ever, held. Da Silva’s popularity has dipped from the astronomically high approval ratings he enjoyed when he left office, but he is still among the most popular politicians in a country where they are scarce. A poll at the end of June, prior to his conviction, showed that he was a favorite to win the presidency again in 2018. His conviction, however, has jeopardized that, since Brazilian law prohibits politicians convicted of crimes from seeking public office. Da Silva has vowed to run anyway. He called himself the “victim of a lie” and said that “only the Brazilian people have the right to decree my end” after the conviction was handed down. But if an appeals court does uphold the conviction, the 2018 race could become a wide-open affair. That concerns Brazilian political experts. Da Silva’s absence from the race could open up space for any number of candidates, and the dueling political and economic crises could create “a temptation to rely on a completely unprepared politician,” Sotero said. One who may be in a position to capitalize on his downfall is Jair Bolsonaro, a member of the Chamber of Deputies from Rio de Janeiro. Bolsonaro, like da Silva, is a populist. Unlike the former president, however, he is a creature of Brazil’s extreme right, a sort of anti-Lula who is opposed to the country’s feminist movements, immigration and programs to promote racial equality. The former Army parachutist has expressed support for the military junta that ruled Brazil from 1964 to 1985, raising concerns that he has the sort of authoritarian streak Brazilian voters have avoided since returning to democratic governance. (Last year, when he cast his vote to impeach Rousseff, he dedicated his action to the man who ran the program that tortured her and many others during the dictatorship.)

Ueslei Marcelino/Reuters Congressman Jair Bolsonaro, who has been described as "Brazil's Donald Trump," is among the candidates who could benefit if former President Lula da Silva can't run in 2018.

“There is the concern that these authoritarian forces might take advantage of this situation,” said Bruno Brandão, the Brazil country manager for Transparency International, a global anti-corruption nonprofit. “They are capturing the discourse of anti-corruption, these populist, authoritarian forces, and trying to profit from the general discontent. They’re using the speech of anti-corruption, and that’s particularly worrisome,” he said. Many experts have dismissed Bolsonaro as an outsider from a small party with little chance of ascending to the presidency. But he has consistently shown up as the second or third most popular choice in early election polls, and his popularity has risen from only a few percentage points last year to as high as 18 percent last month. It’s too early to declare Bolsonaro a real contender, and if da Silva is indeed prevented from running, the former president’s supporters could turn to other, more traditional candidates. But the country’s two largest center/center-right political parties, the PMDB and PSDB, are already wary of Bolsonaro ― as HuffPost Brazil reported last week, they have held discussions about agreeing on a candidate to thwart his rise. For all the global significance of Brazil’s ongoing crises, though, the biggest reason for concern is what they mean for Brazil. Brazil’s recession ― the worst in more than a century ― has devastated the country. A record 14 million Brazilians are out of work, while 3.6 million are in jeopardy of falling back into poverty. Brazil is at risk of returning to the UN’s hunger map in what would be a sad marker for a country that once claimed its policies had nearly eliminated extreme poverty. Ongoing budget problems have created fears that Lula-era social welfare programs could face even more cuts. Human rights groups have warned of rising rates of violence in cities like Rio de Janeiro, where already-high violent crime numbers disproportionately affect the poor, minorities and young people. Operation Car Wash, meanwhile, has paralyzed and demoralized the country. Temer is hanging on to his job but has seen his approval rating fall into the single digits after the corruption allegations against him emerged. In one poll, a near majority of the country’s residents said they were ashamed to be Brazilian. Others have shown declining faith in the government itself, a troubling sign for what is already a “young, fragile democracy,” said Joel Velasco, a former adviser at the U.S. Embassy in Brasilia whose work as a consultant at the Albright-Stonebridge Group focuses largely on Latin America. And now, the man who once exemplified Brazil’s promise ― both to the country and to the world ― has fallen from grace, too. “I think there is some degree of fatigue for all of this,” Velasco said. “That’s what concerns me more. There comes a point where respect for the government is kind of zilch.” “At the end of the day, we do need people to accept that there is a government,” he added. “But if everybody in government is corrupt ― it’s a little similar to the U.S., where ‘Washington is broken’ becomes a campaign motto. But at some point, somebody has to step up and fix Washington.”

EVARISTO SA/AFP/Getty Images Brazil's current president, Michel Temer, has also been the subject of corruption and bribery allegations.