According to Brazil's electoral court, Lula secured 51.79% of the valid votes against Bolsonaro's 48.21%, winning an unprecedented fourth presidential term.
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Sibal argued that the outcome carried significance beyond Brazil, particularly because Lula had resisted pressure from the Trump administration.
"Lula has been at loggerheads with the Trump administration. The latter was openly interfering in the election process by backing Flavio Bolsonaro," he said. "This attempt to put a pro-US government in position in Latin America’s biggest country was an integral part of the Trump administration’s revival of the Monroe Doctrine."
The Monroe Doctrine, first articulated by the United States in 1823, asserted Washington's opposition to European intervention in the Western Hemisphere. The term has more recently been used in debates about American influence over Latin America.
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How Lula stood up to Trump's tariff pressure
Relations between Lula and Trump deteriorated sharply in 2025 after Washington imposed tariffs of up to 50% on Brazilian goods.
The White House justified the additional duties partly by accusing Brazilian authorities of unfairly prosecuting former president Jair Bolsonaro, who faced charges over an alleged attempt to overturn his 2022 election defeat.
Lula rejected the American pressure, arguing that Brazil's judiciary and political institutions were matters of national sovereignty.
In an August 2025 interview with Reuters, Lula said he saw little point in directly approaching Trump while Washington maintained its position.
"The day my intuition says Trump is ready to talk, I won't hesitate to call him," Lula said. "But today my intuition says he doesn't want to talk. And I won't humiliate myself."
Lula's resistance to US pressure became an important part of his political messaging. He portrayed Brazil as a sovereign country that would not accept outside interference in its domestic affairs.
Brazil and India were among the countries hit hardest by Trump's tariff measures in 2025, with duties on some exports reaching 50%.
The tariffs against Brazil were linked partly to its treatment of Jair Bolsonaro and disputes over US technology companies, while additional duties on Indian goods were imposed over New Delhi's purchases of Russian oil.
Why Trump favoured the Bolsonaro camp
Trump has maintained close political ties with the Bolsonaro family, particularly former president Jair Bolsonaro.
Flávio Bolsonaro, Jair's son, emerged as Lula's principal challenger in the 2026 presidential election.
A victory for Flávio was widely seen as likely to bring Brazil closer to Washington on regional security and foreign policy, while Lula favoured greater strategic independence and stronger engagement with developing economies.
The Trump administration had previously imposed tariffs and sanctions while criticising the prosecution of Jair Bolsonaro. Members of the Bolsonaro family also sought American support.
However, Trump stopped short of formally endorsing Flávio during the 2026 election campaign. Reports suggested that his advisers were concerned an explicit endorsement could help Lula mobilise voters opposed to foreign interference.
'Global South would have been weakened'
Sibal said Lula's defeat would have affected the wider grouping of developing countries, particularly because of Brazil's diplomatic weight in Latin America.
"The Global South would have been weakened with Lula’s defeat. Brazil is the strongest voice of the Global South in Latin America," he wrote.
He also argued that a Bolsonaro victory could have created uncertainty over Brazil's commitment to BRICS, the grouping that includes India, Brazil, Russia, China and South Africa among its members.
"BRICS would have been weakened too if the US-promoted right wing had won in Brazil," Sibal said. "Although Flavio Bolsonaro’s father did not walk out of BRICS when he won but today with the Trump administration pressure may have put to do so."
The former foreign secretary also pointed to the growing engagement between Prime Minister Narendra Modi and Lula as a reason the election result could benefit New Delhi.
"Bilaterally too, Lula's victory is a plus for relations with India. The agenda of bilateral ties has become much more substantial with the exchange of visits by Modi and Lula," he said.
India and Brazil have expanded cooperation across trade, defence, energy, agriculture, critical minerals and technology.
Lula visited India in February 2026, when the two countries announced agreements and cooperation initiatives covering areas including rare earths and critical minerals, digital partnership, mining, pharmaceuticals and small businesses.
India-Brazil bilateral trade reached approximately $15.21 billion in 2025, according to India's Ministry of External Affairs.