How is the current government different from any previous governments in 1984? What invention enables it to be like this?

The
government of Oceania differs from prior governments in that it is able to keep its citizens
under constant surveillance due to the invention of the two-way telescreen. Through the
telescreens, Party members can be watched and recorded 24 hours a day. They can even be
addressed, as whenis scolded for doing his exercises poorly. They are subjected as well to
incessant propaganda from the screens.

At the beginning of the novel, Winston
takes advantage of a tiny alcove in his apartment to get out of view of the telescreen, because
normal Party members are never allowed to turn the telescreens off. In fact,and Winston are
utterly astonished whencan do so in his apartment: it is a privilege they can hardly imagine.
Even in the proles' territory, versions of the telescreen intrude. For instance, although they
think they have privacy in their room above Mr. Charrington's shop, Julia and Winston are being
observed and taped from behind a picture on the wall.

This constant
surveillance (or the threat of it) forces people to regulate their private behavior to such an
extent that they have, in essence, no private lives.