Tucker Carlson and an expert on U.S.-China policy discussed Tuesday Google's reported efforts to help the Chinese government potentially censor its citizens' search results. 

In addition, Tucker exclusively reported Tuesday that four House Democrats recently traveled to China with U.S. college students on behalf of what appears to be a Chinese government front group. He said the two-week study trip was meant to "propagandize" the students about China's regime. 

Dr. Michael Pillsbury, author of "The Hundred-Year Marathon: China's Secret Strategy to Replace America As the Global Superpower," said it was a "mistake" for Reps. Sheila Jackson Lee, James Clyburn, Barbara Lee and G.K. Butterfield, to lend their support for such a trip. 

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He then emphasized the seriousness of the controversy surrounding Google's reported development of a search engine that would censor websites and blacklist results on behalf of China's communist government. In addition, the search engine could have linked users' searches to their phone numbers. 

Pillsbury explained that Google co-founder Sergey Brin earned praise for refusing to do business with China's government eight years ago.

"Fast forward eight years and Google has reversed itself, but done so secretly," said Pillsbury, calling on Congress to possibly subpoena Google CEO Sundar Pichai and other top executives for more information on the prototype app-based search engine.

The company declined to make top executives available for a recent Senate Intelligence Committee hearing on election interference, angering lawmakers on both sides. 

Pillsbury said a "hero" employee within Google blew the whistle on the project, leaking internal documents to The Intercept, and explaining that the government of China sought to censor searches for terms like protest, democracy dictatorship and human rights.

Pillsbury said Google is now "highly embarrassed" over the disclosure, adding that only a small number of employees knew about the prototype, code-named Dragonfly.

"I hate to say it's a scandal, we use that word too much in Washington, but it's a growing problem for Google."

A Google spokesman told FoxNews.com, "We've been investing for many years to help Chinese users, from developing Android, through mobile apps such as Google Translate and Files Go, and our developer tools. But our work on search has been exploratory, and we are not close to launching a search product in China."

Watch the compelling interview above.

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