Hillary Clinton has travelled to Shanghai to see for herself the results of her efforts to build up the American pavilion at the World Expo 2010.
The US secretary of state personally helped raise money for the pavilion last year, pleading with US companies to donate the $61m (£42m) needed to build the structure and the exhibit.
The construction of the pavilion was near death when the Obama administration came in, but Mrs Clinton came to the rescue.
She said at the time it would send the wrong message to China if the US was not at the World Expo. The event is at the top of Beijing's political and business and agenda as it seeks to assert itself as a rising power.
In an opinion piece published in the Global Times, a Chinese English language daily, Mrs Clinton also wrote that that "the relationship between the United States and China is critical to both our countries and to the future of our world".
Mrs Clinton will discuss that relationship with Chinese officials in Beijing on Monday and Tuesday, during the second US-Chinese Strategic and Economic Dialogue.
But before the serious talking about thorny issues like North Korea and Iran starts in earnest, she took some time to highlight the positive, and indirectly make a business pitch for American companies in China.
Inside the American pavilion, a rather dull steel structure, visitors are treated to three short movies meant to showcase the "American spirit".
The first one showed various Americans trying to speak Chinese, including famous basketball player Kobe Bryant. The second movie, about the creative power of children, featured representatives from various companies and felt like an ad for corporate America.
It all concludes with a display of all the sponsors who poured the money into the pavilion and a souvenir shop where everything seemed to be "Made in China".
Increasing exports to China is a key goal of the Obama administration to improve the US economy but, privately, some of the US officials in the delegation seemed a bit disappointed by the bold branding of the exhibit.
The US pavilion has received a lot of negative coverage in the US press, particularly because of the corporate financing, which is unusual for national pavilions.
But it appears to be a success in China and is one of the most visited at the fair, with 700,000 visitors since the opening just under a month ago. Just over 400,000 people have visited the Russian pavilion. It is expected the fair will receive 70 million people in total over six months.
Mrs Clinton said little about the impression the US pavilion had made on her. Later in the day, she met Chinese-speaking American students who are acting as "ambassadors" at the fair, and told them only that she "liked it".
But she added that she "was relieved because it was not clear at all, when I became secretary, that we would have a pavilion. And I thought that would not be a good representation of our country at this important time history at this event".
Mrs Clinton said it was not possible to be present at all the World Expos, but some were more important than others. The simple fact of being at the expo seemed to be enough of an achievement.
"To have six or seven million young Chinese to file through our pavilion is an opportunity that we would otherwise never be able to achieve in public diplomacy, at least not traditional public diplomacy," the US ambassador to China, Jon Huntsman, told the BBC.
"And if that results in better relations, if it results in better attitudes to the United States and certain buying preferences, then you get a bit of public diplomacy and you get a bit of commercial diplomacy."
Mrs Clinton also toured the Chinese pavilion, the biggest at the fair, featuring a massive red inverted pyramid with elaborate exhibits for the 31 Chinese provinces.
The building had remained open to the public and she was greeted everywhere by excited Chinese people, some of them screaming: "We love you Hillary."
Ten minutes away from the China pavilion stood the exhibits of two of America's foes.
For its first participation in a World Expo, North Korea's exhibit featured a fountain and a fake moat, but no-one was queuing to get in.
Right next door was Iran's more popular exhibit.
Inside, a huge picture of Iran's political and religious leadership at prayer, including President Mahmoud Ahmadinejad and spiritual leader Ayatollah Ali Khamenei, covered one of the walls.
Traditional Iranian music performances were also on offer six times a day, and Iranian rugs were on sale on the upper level.