Key Bolsonaro lieutenant blasts Biden for silence on Brazil’s X ban: US has ‘responsibility’ to speak up

It appears that you're referencing a situation where someone close to Brazil's President Jair Bolsonaro has criticized US President Joe Biden for not speaking up about a certain issue in Brazil labelled as "X". Without more specific details about what "X" refers to, it's hard to provide a more exact explanation. The reference to the US having a 'responsibility' to speak up could suggest that "X" is a significant issue or policy impacting international relations, human rights, or environmental conservation.