2) Deciding what to break up

In past marquee antitrust cases, the road map for a breakup was relatively straightforward. The Standard Oil case, decided by the Supreme Court in 1911, saw that company split up largely along geographic lines. AT&T was a heavily regulated company with separate businesses for long-distance and local telephone lines, making the lines of division clear.

Facebook doesn’t have such easily identifiable boundaries. Social networking works only through reaching as many people as possible and connecting them with others, making the idea of separating parts of the business much more complex.

“In the internet age, those kinds of options just don’t exist,” said Andrew Schwartzman, an attorney with Georgetown’s Institute for Public Representation.

Critics like Warren and Hughes have talked up the idea of cleaving off Instagram and WhatsApp, which Facebook acquired in 2012 and 2014, respectively. Even though they appear to consumers as distinct apps, however, they are already deeply integrated with Facebook. Instagram, for example, uses the same advertising technology as Facebook.