Brazil bans Twitter because it is "dangerous" and a "threat" to democracy.

Your logic is the excuse totalitarian tyrants use every single time.

The Nazi's ...

The Chinese during the Marxist takeover (Great Leap not-Foward, and the Chinese Cultural Destruction Revolution of the 60's) ...

The Russian's dyring the destruction under the Lenin Marxists ...

They all claimed speech to be "harmful", "dangerous" and a "threat" to democracy.