When Laura Bush ventured to the Thailand-Myanmar border six years ago, the first lady accused China of not doing enough to pressure the brutal Myanmar regime. When Hillary Rodham Clinton visited Beijing in 1995, she delivered a blunt assessment of China's human rights record.
But as Michelle Obama prepares to journey to China next week with her mother and daughters, she does not plan to deliver a similar performance.
Obama's decision to focus on educating young people - a consistent theme in her rare solo foreign trips - reflects a broader decision to steer clear of political controversies, even after her husband has run his last campaign.
It reflects a strategy she adopted early in her husband's tenure, which was to develop long-term campaigns around specific issues such as obesity, youth empowerment and education, rather than using her position as a bully pulpit.
"This was her decision - not a political one, in the sense that she decided to play it safe," a former senior US administration official wrote in an e-mail. "She never wants to show up somewhere and just make a speech."
Obama's effort to avoid controversy is particularly pronounced on the China trip because of the country's complicated relationship with the United States.
The two are global competitors, and the Chinese government's human rights record crops up during almost every high-level meeting between the two countries.
This year, for example, Ilham Tohti - an economics professor and outspoken advocate for the Uyghur Muslim minority - was arrested and charged with separatism, prompting US officials to again urge China to respect the rights of political activists.
Gary Locke, the outgoing US ambassador at the time, raised the case of Tohti and other activists in his final news conference in Beijing.
Back in 2003, Clinton took direct aim at China's human rights record during the United Nations' Fourth World Conference on Women in Beijing, where she spoke at length about the injustice of forced abortions and sterilisations and suppressing free speech.
"It is time to break our silence," she told a packed audience without naming China directly. "It is time for us to say here in Beijing, and the world to hear, that it is no longer acceptable to discuss women's rights as separate from human rights."
Other presidential spouses have confronted repressive regimes as well.
Laura Bush embraced the cause of Myanmar, holding an unprecedented news conference at the White House urging the country's isolated military junta to accept help after Cyclone Nargis. Three months later, she made the trip to Myanmar's border on her way to the 2008 Olympics in Beijing.
"We urge the Chinese to do what other countries have done - to sanction, to put a financial squeeze on the Burmese generals," she said in Thailand.
Obama, by contrast, will devote her trip, from March 19-26, to visiting two high schools and a university and seeing China's historic and cultural sites, such as the terracotta warriors in Xian.
Speaking at a ceremony at the State Department last week, she said she would emphasise the same themes in China that she did during past visits to Mexico and southern Africa.
"I make it a priority to talk to young people about the power of education to help them achieve their aspirations," she said. "That message of cultural exchange is the focus of all of my international travel."
Obama's approach most closely echoes that of Barbara Bush, who avoided overtly political issues as first lady. In her memoir, Bush calls a dinner invitation to Chinese dissident Fang Lizhi a "gaffe".
Chinese security blocked Fang from attending the banquet, but Bush writes that she wished the invitation had never been proffered.
Bonnie Glaser, a senior adviser for Asia at the Centre for Strategic and International Studies, said the Chinese would welcome the idea of a politics-free visit.
"The Chinese will be quite eager to keep any political comments or anything that would reflect negatively on their political system off the table," Glaser said.
In a White House blog post announcing the visit, Obama did raise the prospect of discussing some basic freedoms: "I'll be talking with students about their lives in China and telling them about America and the values we hold dear."
A senior administration official said the first lady would raise the issue of freedom of expression in the context of "education and youth empowerment" and "the strength of our system contrasted with those of the Chinese".