The biggest tech deal in history is at risk over increased scrutiny by antitrust enforcers within the Federal Trade Commission, led by a 33-year-old legal scholar and prominent Big Tech critic. Chair Lina Khan has in her crosshairs Microsoft’s $68.7 billion acquisition of Activision Blizzard, and it’s not her only target. The agency is also reportedly looking into Elon Musk’s Twitter takeover.

Since President Joe Biden’s controversial appointment of Khan to head the FTC less than one year ago, Khan has been on a mission to rein in Big Tech. But even before her ascension to the chair, she was one of the most prominent voices calling for an end to Big Tech supremacy. Her first notable target was Amazon.

“This is actually also causing economic harm, a lot of the small businesses that are dependent on Amazon are terrified,” then-28-year-old Khan said in an interview with Fox Business.

Khan’s meteoric rise began in 2017 when a paper she wrote in the Yale Law Journal, Amazon’s Antitrust Paradox, went viral. Her own hardline antitrust positions detailed there began a new wave of antitrust enforcement as people adopted her views. And in just four years, Khan went from law school to counsel to the U.S. House Judiciary Subcommittee investigating Big Tech to Columbia Law professor to FTC chair. Now her opinions on mergers and monopolies carry even greater weight.

“Industry consolidation and weakened competition have denied Americans the benefits of an open economy, with workers, farmers, small businesses and consumers paying the price,” Khan said earlier this year.

“She has a very strong competence around this topic,” Congressional Progressive Caucus Chair Rep. Pramila Jayapal (D-WA) said.

Progressives may love Khan but tech giants are pushing back, accusing her of showing bias against Big Tech long before she was appointed head of the FTC. Facebook and Amazon have both previously requested Khan’s recusal from any cases or investigations related to the companies, questioning her ability to be objective in the role based on her previous statements.

“I think there’s good evidence that Amazon’s been abusing forms of its conflicts of interest that we should address as a society,” Khan said in 2017.

She has faced her fair share of pushback in politics, too. Sen. Mike Lee (R-UT) said the FTC under Khan is launching “a progressive putsch to consolidate power and burden American businesses.” And the Wall Street Journal editorial board called Khan “a 32-year-old academic who has no experience running anything.”

Now nearly a year into the gig, it appears the criticism is rolling off Khan’s back, along with calls for recusal.

“We’re really showing these companies, but also showing the country, that enforcers are not going to back down because of these companies flexing some muscle or kind of trying to intimidate us,” Khan said during an exclusive interview with CNBC.

Khan’s philosophy is a big departure from the last two decades, when Big Tech gobbled up hundreds of smaller firms. But Biden is standing by her and her antitrust views, giving her the power, agenda and support to revise the landscape of American capitalism.