On Monday, US President Barack Obama started his second four-year term. His country is currently suffering both economic weakness and political paralysis. As a reelected president, he knows how difficult it is to effect change in the biggest economy in the world.

Obama shouted slogans of "change" when he entered the White House four years ago. Four years have passed, but almost no change has been achieved. Wall Street remains the same and reforms to the healthcare system remain troubled.

Contradictions within US society have gradually caused the system to become more rigid in response to the discontent that Americans can fully express.

Four years ago, Obama impressed many people with his demeanor and eloquence. But he has yet to make a mark on history.

This doesn't mean that Obama is a failure, instead, it reflects the fact that it is becoming increasingly difficult to manage the US. There are too many forces holding Obama back and Americans have high demands.

The US is standing at the commanding heights of development of human society. It can just bide its time for four years. However, if China were managed by similar methods, the result would be totally different.

China also has a super-sized management system which is less powerful than that of the US, but the US does not have as many contradictions within society as China.

These contradictions were buried previously, and they have gradually emerged. China is no longer a country where the government's call is immediately taken up by all of society.

Compared with the US, obviously China has changed more in the last four years. We have gotten used to the fact that the changes are growing larger and larger. Almost all social policies are being adjusted to improve people's livelihood and enhance equity.

Meanwhile, enthusiasm for debate has also been aroused in China and democracy is developing rapidly. These add vitality to Chinese society and break the façade that the country is totally united on all issues.

It is a good thing for China, but at the same time, it is also very new. It will be a long-term test for China to grasp the new situation and use these positive aspects at a political and ideological level for achievements in terms of people's livelihoods.

Both China and the US are countries which face challenges in governance. However, the US can afford to do nothing while China must continue to move forward.

China has learnt a lot from the US since the reform and opening up. But it must also take a lesson from the US financial crisis that debates cannot be endless. China must have the power to make decisions and carry them out.

China has already entered into the era when all decisions will receive opposition.

Against such a background, if we want to develop healthily in the 21st century, the most important rule is that this country should be gradually become democratic. But Chinese society cannot exist in a state of disunity.

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