Don't think they have much to fear from the Argies, the Guayanese, or the Paraguayans (except for dope from the latter). This is all about becoming a regional power with an independent foreign policy, expanding its sphere of influence down the line. Due to a lack of cultural or historical ties with its neighbors, however, I don't see Brazil leading a "Latin American block." Its economy is large enough that such a development is irrelevant at this point. This is all about Brazil's "coming out" as an emerging power, per the current leadership.
Keep in mind that Brazil is filled with anti-nuclear peaceniks just like the US and Europe are. Be interesting to see how the larger society views this, however. Brazilians are generally patriotic, but are also anti-militaristic, even though many were just children, or weren't even born during the dictatorship.
