Facebook chief executive Mark Zuckerberg at F8, Facebook's developer conference, in San Jose on May 1. (Marcio Jose Sanchez/AP)

WHAT HAPPENS now? That is the essential question following the New York Times’s troubling investigation into Facebook’s response to Russian interference on its platform. The article has prompted sharp criticism of the company from all quarters, and Facebook deserves the blowback. But Americans deserve solutions. There are a few places to start.

Facebook has disputed the Times’s characterization of its efforts to combat Moscow’s meddling, which the paper reports were worse than insufficient. According to the Times, executives not only sought to play down the degree to which Russians had used Facebook to manipulate American voters but also embarked on a campaign to discredit critics and turn attention toward other companies.

Most concerning is Facebook’s hiring of a public-relations firm, Definers, that played into conspiracy theories by linking grass-roots opposition to billionaire George Soros — while Facebook also lobbied a Jewish civil rights group to cast other negative rhetoric as anti-Semitic. These tactics exploit one of America’s deepest divides, amplifying the same political polarization Facebook claims it is trying to stop its platform from promoting. (Facebook CEO Mark Zuckerberg says he and chief operating officer Sheryl Sandberg were unaware of Definers’s involvement.)

It is strategies such as these that make it difficult to write off Facebook’s failings as part of a maturation process for the Silicon Valley start-up turned titan. Facebook may finally be wrapping its head around its responsibilities, but it refused to until it began to fear a regulatory onslaught, and even then, it went to great lengths to avoid a reckoning.

This reality underscores the need for Congress to keep pushing, even as Facebook takes strides of its own in policing its platform and keeping the public apprised of what that work looks like. The company announced Thursday that it would expand its appeals process for removals. Facebook will also start demoting “sensationalist and provocative content” that skirts its terms of service but does not violate them. And it will continue releasing transparency reports on the accounts and posts it does end up taking down.

These are all worthy endeavors. Congress’s role is to continue applying pressure to Facebook to ensure the company lives up to its promises — and to step in when it does not. Some areas for intervention are obvious: The Honest Ads Act, currently stalled in the Senate, would stop advertisers from hiding their identities from users. A robust federal privacy law would protect consumers’ data against incursions such as the Cambridge Analytica breach revealed this year.

At the core of the conversation, however, is a stickier subject: speech. There is danger in asking government to weigh in on what civilians can say and where they can say it. But whether Facebook can succeed on its own — without, at least, rules such as those Mr. Zuckerberg himself has proposed requiring companies to report the prevalence of malicious content on their sites and setting thresholds for reduction — seems less certain than ever before. Congress’s role over the next year will be to determine, through ceaseless scrutiny, whether the company is up to the task.