With China drawing criticism from candidates in the US presidential election and Beijing changing Communist Party leaders next year, Locke said the Obama administration would work to maintain forward momentum in relations, including coaxing China to open up wider to US exports and investment to create more American jobs.
In an interview, Locke reflected on his four months as the top US diplomat in China, from efforts to cut the time Chinese have to wait to get visas, to cooperation on clean energy research, to his own unexpected celebrity as the first Chinese-American ambassador.
"When we're having lunch with the family ... or we're going to a supermarket, we're stopped by people who want pictures, even at the airport or on an airplane," Locke said at the US Embassy during a lunch of sandwiches and pasta salad, indicative of his down-to-earth personal style that has won him kudos from many among the Chinese public.
Locke said the Foreign Ministry has summoned him only once for a dressing down, late one September night over the administration's decision to upgrade the US-made F-16 fighter jets of Taiwan, the self-ruled island democracy claimed by China.
Long involved in China issues, first as governor of Washington state and then as commerce secretary, Locke described Beijing's reaction to the $5.85 billion deal as strong, but overall relations did not plummet the way they had after some previous US arms sales. Recent initiatives by President Barack Obama to strengthen the US military alliances with Australia and other countries on China's edge have not caused undue friction, he said, signs of the breadth of ties between the world's largest and second-largest economies.
"The US-China relationship is certainly stronger than ever before, much more complex than ever before. The economies of China and the US have become much more sophisticated and much more complex" since the start of diplomatic relations 33 years ago, Locke said.
However, Locke expressed strong concerns over China's rights record, saying abuses had been rising over the past year as Chinese leaders worried that the democratic uprisings that swept Egypt and other Arab countries might spread to China. He cited the widespread detention and arrest of activists and lawyers and a lack of judicial independence.
"It's getting worse. I think certainly the last several months, or actually the last year or so, we've seen developments and incidents that give us great pause and a great deal of concern," Locke said.
Locke said he has met with a wide range of activists, lawyers and religious leaders and sensed they were uneasy to discuss not only sensitive topics such as controls on religion but also mundane ones such as raising incomes and living standards for women and migrant workers.
The embassy's deputy chief of mission tried to meet in the last two weeks with Liu Xia - the wife of imprisoned Nobel Peace Prize laureate Liu Xiaobo who herself is under house arrest - but was stopped from doing so, Locke said.
"So we are monitoring these cases. We are trying to meet with individuals as much as we can," he said. Locke said he has continued to raise the case of jailed American geologist Xue Feng, visiting him twice. He said the case highlights the abuse of the legal system in China.
Though Locke said he reached out to human rights lobbyists soon after Obama selected him as ambassador last February, he has been seen as being more comfortable with business and trade issues. The rights community has criticized him for not being as visible an advocate as his predecessor, would-be Republican presidential candidate Jon Hunstman.
Being of Chinese ancestry - his grandfather emigrated from southern China and worked as a servant - has made Locke's tenure as ambassador unusual. From before he boarded the plane to take up the post in August, he has been in the spotlight; someone photographed him buying coffee in a Starbucks in Seattle and posted it on the Internet.
He has won wide admiration in social media. That he carries his own knapsack, buys coffee and travels economy class has drawn favorable comparisons with Chinese officials, who often travel first class and in the company of fawning assistants. The more nationalistic state media have questioned whether these habits are part of a plan to defame China, and editors and reporters have said they have been told not to give Locke too much prominence in their reporting.
"Who would have thought that just getting a cup of coffee would create such a stir," Locke said.
Another unexpected controversy has been over Beijing's often dismal air quality. The US Embassy publishes on the Internet and Twitter readings from a rooftop monitor. The results are frequently at odds with Beijing's official data and are being used by local Chinese to prod their government into doing something.
Locke said he has been surprised by the awful air when he walks the family dog at night or takes his three children to the school bus in the morning. He said no Chinese official has complained to him about the data, though state media have.
"We get questions from the Chinese media about whether we're trying to sow discontent," Locke said.