Tamar Jacoby: The FTC is taking on some of the biggest, most powerful companies in the world. She says they have resources to throw at attacking or trying to intimidate law enforcers that are just trying to do their jobs. There's a bipartisan realignment where we see significant concern about how monopoly power is hurting our economy, she says. "I knew up when I signed up for this job that if you're looking to take on monopolies, as Congress instructed us to do"