China has nothing to prove in this case, as it asked to be part of the International Space Station. This request was shut down by the US Government, which now prevents NASA from working with any Chinese citizen affiliated with the government (e.g. CNSA). This is entirely on the US and it's decision to bar the CNSA from any cooperation with NASA, and not on a Chinese reluctance to be part of the CNSA.

From NASA chief says ban on Chinese partnerships is temporary (Reuters, 12 Oct 2015):

The United States should include China in its human space projects or face being left out of new ventures to send people beyond the International Space Station, NASA chief Charles Bolden said on Monday.
Since 2011, the U.S. space agency has been banned by Congress from collaborating with China, due to human rights issues and national security concerns.

From Politics of the International Space Station (Wikipedia):

In 2007, Chinese vice-minister of science and technology Li Xueyong said that China would like to participate in the ISS.
In 2010, ESA Director-General Jean-Jacques Dordain stated his agency was ready to propose to the other 4 partners that China be invited to join the partnership, but that this needs to be a collective decision by all the current partners. While ESA is open to China's inclusion, the US is against it.

From The Silly Reason the Chinese Aren't Allowed on the Space Station (Time, 29 May 2015):

China has been barred from the ISS since 2011, when Congress passed a law prohibiting official American contact with the Chinese space program due to concerns about national security.

More info e.g. here

China has nothing to prove in this case, as it asked to be part of the International Space Station. This request was shut down by the US Government, which now prevents NASA from working with any Chinese citizen affiliated with the government (e.g. CNSA). This is entirely on the US and its decision to bar the CNSA from any cooperation with NASA, and not on a Chinese reluctance to be part of the CNSA.

From NASA chief says ban on Chinese partnerships is temporary (Reuters, 12 Oct 2015):

The United States should include China in its human space projects or face being left out of new ventures to send people beyond the International Space Station, NASA chief Charles Bolden said on Monday.
Since 2011, the U.S. space agency has been banned by Congress from collaborating with China, due to human rights issues and national security concerns.

From Politics of the International Space Station (Wikipedia):

In 2007, Chinese vice-minister of science and technology Li Xueyong said that China would like to participate in the ISS.
In 2010, ESA Director-General Jean-Jacques Dordain stated his agency was ready to propose to the other 4 partners that China be invited to join the partnership, but that this needs to be a collective decision by all the current partners. While ESA is open to China's inclusion, the US is against it.

From The Silly Reason the Chinese Aren't Allowed on the Space Station (Time, 29 May 2015):

China has been barred from the ISS since 2011, when Congress passed a law prohibiting official American contact with the Chinese space program due to concerns about national security.

More info e.g. here

I disagree with Abhishek's post—China has nothing to prove in this case, as it asked to be part of the International Space Station. This request was shut down by the US Government, which now prevents NASA from working with any Chinese citizen affiliated with the government (e.g. CNSA). This is entirely on the US and it's decision to bar the CNSA from any cooperation with NASA, and not on a Chinese reluctance to be part of the CNSA.

China has nothing to prove in this case, as it asked to be part of the International Space Station. This request was shut down by the US Government, which now prevents NASA from working with any Chinese citizen affiliated with the government (e.g. CNSA). This is entirely on the US and it's decision to bar the CNSA from any cooperation with NASA, and not on a Chinese reluctance to be part of the CNSA.

From NASA chief says ban on Chinese partnerships is temporary (Reuters, 12 Oct 2015):

The United States should include China in its human space projects or face being left out of new ventures to send people beyond the International Space Station, NASA chief Charles Bolden said on Monday.
Since 2011, the U.S. space agency has been banned by Congress from collaborating with China, due to human rights issues and national security concerns.

From Politics of the International Space Station (Wikipedia):

In 2007, Chinese vice-minister of science and technology Li Xueyong said that China would like to participate in the ISS.
In 2010, ESA Director-General Jean-Jacques Dordain stated his agency was ready to propose to the other 4 partners that China be invited to join the partnership, but that this needs to be a collective decision by all the current partners. While ESA is open to China's inclusion, the US is against it.

From The Silly Reason the Chinese Aren't Allowed on the Space Station (Time, 29 May 2015):

China has been barred from the ISS since 2011, when Congress passed a law prohibiting official American contact with the Chinese space program due to concerns about national security.

More info e.g. here