AT&T Forbids Criticism

In its latest Terms of Service (ADSL) that its clients must obligatorily accept, AT&T has added a unbelievable clause.
It authorises them to disconnect the service of clients who had the impertinence to openly criticise them, or more precisely "for conduct that AT&T believes [...] tends to damage the name or reputation of AT&T, or its parents, affiliates and subsidiaries."
Definitely, the stupidity seems unlimited, and those who had the idea for this clause would be better off finding a job in a dictatorship. They are clearly of the disposition to exercise their profession in that type of regime.
[update] It seems that most US ISPs and carriers have in their legal policies this type of clauses, which look crazy seen on that side of the Atlantic. In EU such clauses could simply not exist for such contract, probably because customer rights are better protected.