China's change of tone
In one crucial respect this state visit appears to have been a success. It has, for now, halted a damaging deterioration in China's relations with America.
There were no major breakthroughs, no real sense or warmth. But after a year in which an increasingly assertive China had alarmed and alienated many in Washington, ties appear to be on a more constructive footing.
President Barack Obama managed to deliver some tough messages on human rights and the economy, while giving President Hu the respect China's leaders crave abroad.
President Hu Jintao was careful to try to sound reassuring to Americans. China's rise, he said, was good for America, it would not engage in an arms race or pose a military threat.
It was in striking contrast to the shrill, sometimes aggrieved tone China has taken with America of late.
That tone has been evident over any number of issues, whether US arms sales to Taiwan, Mr Obama's meeting with the Dalai Lama, the Nobel Peace Prize, Google, the South China Sea.
And on the American side President Obama was at pains to stress the way America can benefit from a co-operative rather than a confrontational relationship with China.
Congress is full of voices that criticise China. Mr Obama provided a counterpoint and made the case to Americans for welcoming China's rise.
Some of this seems to have come about because China's priority was to ensure that the state visit passed off successfully at all costs. It didn't want any public arguments or loss of face.
So the tone was carefully managed throughout. Beijing sought to minimise sources of friction even before heading to Washington - the People's Bank shifted the Yuan's exchange rate to record highs ahead of the visit, Beijing began to pressure North Korea more and President Hu was prepared to address human rights.
Some of the softer tone was, I think, because China seems to be to taking steps to improve the management of its public relations abroad.
I don't think it's a coincidence that President Hu tried to hit a gentler tone while at the same time China paid for advertisements to be played on the big screens in Times Square in New York.
But the shift is also perhaps a reflection of the fact that America has been willing to be more blunt with Beijing. The best example of this is over North Korea.
America really is worried about the combined threat posed by North Korea's nuclear programme, its missile development and its recent more aggressive behaviour. That all adds up to a growing problem seen from Washington.
The Obama administration, it seems, was prepared to tell China directly that if Beijing doesn't address the threat and use its leverage over North Korea, then America will act.
That may mean a more aggressive American military posture in East Asia, something China definitely doesn't want to see. So the message to China was something like this: your rising power means you have a rising responsibility to act, if you ignore the problem there will be costs to your inaction.
The interesting thing here is that we are already seeing movement in the situation on the Korean peninsula. If a rising China is starting to accept a broader role, that would be a major result of this state visit. But it's early days.
And it's worth remembering that, on this issue, China and America have not been that far apart. Both agreed some time ago that North Korea is a worry - they disagreed over how best to deal with it.
And there are still many other major disputes between the two nations, over China's exchange-rate policies, access to its markets, rampant theft of intellectual property in China, America's weapons sales to Taiwan and its restrictions on high technology exports, to name a few.
So this is clearly not a G2, not a close and co-operative partnership between the world's two biggest economies.
And the US administration is likely to be cautious, to bide its time and see if warm words by a Chinese leader abroad translate into a new approach back in Beijing.