WASHINGTON — Sen. Ben Cardin criticized U.S. leaders for not taking a more aggressive stance on China’s human rights issues during President Xi Jinping’s official state visit.

“I was disappointed in this summit that there is no visibility on the human rights front,” said Cardin, ranking member of the Foreign Relations Committee. “I think it is a major failure.”

The United States has long promoted human rights issues in China, calling for more religious, press and Internet freedom. Western media compared the Chinese government’s crackdown on the protests in Hong Kong last December with the Tiananmen Square tragedy in 1989.

China responded to U.S. barbs by issuing a human rights report last year, critiquing the record of United States. The report highlighted the easy availability of firearms and racial discrimination in America.

On Tuesday, Sen. Cardin, D-Md., told a Foreign Relations Committee hearing he wasn’t impressed with how the State Department or either political party handled Xi Jinping’s visit, which ended Monday.

“There is always the obligatory comments made by our leaders just to say we didn’t forget the subject, although you question how aggressively it is raised in the bilateral,” Cardin said at the hearing on U.S- China relations.

However, one witness at the hearing, Melanie Hart, head of China Policy at Center for American Progress, had a different view. “I think it is important to distinguish between effectiveness and noise,” she said of the less confrontational stance taken during Xi’s time in Washington. “With China, sometimes the most effective actions are quiet actions.”

Hart, who holds a Ph.d in political science from the University of California San Diego and formerly worked for the Aspen Institute, argued that “one of the most impactful things the U.S. has done over the past decade is installed an air quality monitor device on the U.S. Embassy in Beijing and put the data on Twitter.”

That simple action had a ripple effect, she said. “Chinese people who have VPN and could access Twitter, could begin monitoring the air quality data.”

Progress is being made, Hart maintained. She said before carrying out some of its new laws, China sent draft copies to American media and think tanks, gathering opinions. That was “never seen” a decade ago, she said.

China issued a draft Environmental Protection Tax Law in June in response to serious pollution problems. During his visit, President Xi also confirmed China’s plan to launch a national emissions trading system in 2017.

Cardin wasn’t buying it, arguing environmental issues were more visible than human rights issues.

“Meanwhile people are in prison, meanwhile people can’t practice their religion, meanwhile journalists are being denied access, meanwhile the Internet freedoms are being taken away…” the senator told Hart, “And I don’t know how much patience we should have on this.”

Hart replied: “The most important patience indicator is the patience of the Chinese people. I think we need to look to them as our guide on what’s best for their nation.”

Cardin still was not satisfied. “So when they get upset like Tiananmen Square, we see violence and we see rights taken away. Protests don’t work in China…” he said.

“I am not convinced that China will allow their people to speak.”

The United States must lead on human rights issues, Cardin insisted. “If we don’t lead, the rest of the world won’t.”