Assuming that the governments really could just manipulate the root at will(every root, which is many machines, remember)... the only thing they could do is break DNSSEC. The DS hints would not match the KSK of the tld zone otherwise...unless of course every government in the world was in on it together...illuminati, free-masons, oh the Rothchilds are in on it too I think.
Seriously, this is a borderline absurd statement. The only way to manipulate the root in a way that allows DNSSEC to work otherwise is to redirect all traffic for every tld to new government owned servers with a matching KSK in place. Not very realistic.
