Laura Rosenberger is director of the Alliance for Securing Democracy and a senior fellow at the German Marshall Fund of the United States. Zack Cooper is co-director of the Alliance for Securing Democracy and a research fellow at the American Enterprise Institute.

In recent weeks, the world has watched as millions of Hong Kongers have taken to the streets to defend their democratic rights. Police have jailed protest leaders, and China has moved troops to the border. The struggle has also spread to online platforms, which Beijing is using to shape perceptions of the protests in order to undermine support for them.

Although Hong Kong’s chief executive Carrie Lam has addressed one of the key demands from protesters, the protests continue. Even if protests dissipate, we should anticipate that Beijing will use the next few months to better understand how demonstrators used online platforms to organize, constrict further online activism and manipulate perceptions of the protesters.

The Chinese security apparatus is deeply experienced in restricting speech online, starting inside its own borders and with its own platforms. Western tech companies have now confirmed that the Chinese government is also engaged in an effort to manipulate the information space outside its Great Firewall, from Hong Kong to Melbourne to Vancouver. In the process it is also making use of U.S. social media platforms. This should serve as a wake-up call for Americans that weaponization of social media is not just a Russian tactic and that our social media platforms remain vulnerable to manipulation by foreign actors seeking to interfere in democratic debate.

The first public evidence of this campaign was confirmed several weeks ago when Twitter, Facebook and Google’s YouTube disabled more than one thousand accounts linked to Chinese state-backed information operations. According to the companies, these accounts are operating in a “coordinated manner” and “deliberately and specifically attempting to sow political discord in Hong Kong.” Beijing’s target certainly wasn’t citizens in mainland China, where all three platforms are blocked.

China has also been using its state media — as well as advertisements on social media platforms — to portray the protesters as violent to external audiences. In the face of this activity, Twitter took the commendable action of halting advertisements from state-controlled media outlets.

Beijing and other authoritarian regimes are increasingly employing these techniques. Facebook and Twitter have removed numerous fake accounts linked to Iran, Saudi Arabia, Venezuela and Myanmar for similar manipulative behavior.

Nor is this just about democratic rights in Hong Kong. Australia and most of our European allies have struggled to prevent external interference in their democratic processes, and Taiwan is rightly concerned that the manipulation and interference tactics Beijing is exerting in Hong Kong will be used to interfere in its elections next year. And we know that social media has been used to attack American democracy.

All Americans can agree on the need to take action to protect our system of government. A competition of ideas is healthy, but foreign interference in those debates is not. The 2020 elections are likely to be even more contentious than those in 2016, so we need to ensure the health of our political processes.

Despite these shared concerns, our elected leaders have taken few steps to safeguard our democracy, including from foreign manipulation of social media. To date, Congress has shown both a thin understanding of technology and a greater interest in scoring partisan points than in addressing real challenges. Numerous pieces of bipartisan legislation have gone nowhere, while foreign adversaries have continued their assault on our democratic debate. As Congress returns this month, there are several immediate steps it should take.

First, lawmakers should enact measures that facilitate greater cooperation and transparency by social media platforms. Congress should pass legislation establishing a mechanism that streamlines and institutionalizes information sharing between and among the social media platforms, government and outside researchers in a manner that protects privacy and speech. Legislation such as the bipartisan Honest Ads Act would improve disclosure requirements for online political advertisements and provide Americans with important context to evaluate information about who funds political ads online.

Second, Congress should provide the government with mechanisms to facilitate a coordinated and integrated approach to this issue — one that enables it to see and respond to the full threat picture. This should include creating a counter-foreign interference coordinator at the National Security Council, which would coordinate policy responses across the U.S. government and engage the private sector, and a National Hybrid Threat Center, which would ensure that threat reporting does not fall into gaps and seams as it has in the past. Congress should explore whether the intelligence community should receive new powers to detect and assess foreign information operations.

Third, Congress should send a clear message to foreign governments, entities and individuals that the United States will impose significant costs for interference. And it should support efforts to redouble coordination with our allies on the shared challenges facing our democracies.

China is using U.S. social media platforms to manipulate how people around the world, including Americans, perceive issues of importance to the party-state. Right now the focus is on Hong Kong, but it won’t stay there. Our elected leaders can get ahead of the curve and close the vulnerabilities China’s information operations will exploit. To preserve the vitality of our free and open democratic process, they should — and now.

Read more:

The Post’s View: The U.S. government needs to protect against 2020 election meddling

The Post’s View: Americans deserve to know who pays for political ads. But is that enough?

The Post’s View: China keeps booting U.S. journalists. We keep admitting theirs.

Marco Rubio: China is showing its true nature in Hong Kong. The U.S. must not watch from the sidelines.

Jennifer Rubin: Trump betrays his country again by inviting foreign interference