The world has been watching events unfold in Hong Kong in recent weeks, after tens of thousands of pro-democracy protesters took to the streets to occupy key locations in the heart of this financial hub.
Much of the international reaction has been supportive of the protesters' aims. Foreign governments, meanwhile, have been working out what to say publicly.
They should comment. Hong Kong is a global city, whose political development has wider implications, not least for international economic and commercial interests in Asia and beyond.
But comments by some politicians and media commentators in recent weeks demonstrated a worrying lack of understanding of the relevant historical agreements and Hong Kong's status as a Chinese territory - albeit with significant autonomy. This is unhelpful to the rebuilding of trust that is needed if any progress is to be made in Hong Kong.
For the UK, as the former colonial power until it handed control to China in 1997, the diplomatic challenges presented by the protests are that much sharper. The shadow of the 1984 Sino-British Joint Declaration hangs over policy makers - this is the agreement under which Hong Kong maintains its own system as part of China, a 'one country, two systems' concept fleshed out in the Chinese Basic Law of 1990, Hong Kong's mini-constitution.
The protests were fuelled by dissatisfaction with the Hong Kong government, but the catalyst was the 31 August decision of China's national legislature - the National People's Congress Standing Committee - on Hong Kong's constitutional development.
The key issue of contention is not whether Hong Kong people should have a say in the choice of their next chief executive (head of government) in 2017 - Beijing has already agreed to allow a popular vote. The controversy is over how candidates should be nominated.
The central authorities see a role for themselves as being in line with the Basic Law, one of the few manifestations of 'one country' when it comes to a political structure which is otherwise formed locally in Hong Kong. As a result, the 31 August decision provides for a 1,200-strong nominating committee, half of whose members must approve candidates to appear on the subsequent popular ballot. The committee's constitution means that it is a broadly pro-establishment body, and this is where Beijing (and Hong Kong's elites) can effectively screen out candidates.
Views in Hong Kong are divided. But a sizable proportion of people want more, effectively demanding greater autonomy by rejecting any way for Beijing to influence nominations, or by seeking to dilute the nominating committee's role. These aspirations are understandable given the nature of Hong Kong society and a desire for better governance.
The problem is that they are not easily attainable within the framework of the Basic Law. Without compromise, Hong Kong could be facing something of a constitutional crisis.
How does this debate match up to those historical agreements?
Contrary to what some are saying, the proposals on the table do not contravene what was agreed between China and the UK. All the Joint Declaration said is that the chief executive will be 'appointed by the central people's government on the basis of the results of elections or consultations to be held locally [in Hong Kong]'. Britain's role as co-signatory of that agreement gives it no legal basis for complaint on this particular point, and the lack of democracy for the executive branch before 1997 leaves it little moral high ground either.
It is the Basic Law that introduces 'the ultimate aim [of] the selection of the chief executive by universal suffrage upon nomination by a broadly representative nominating committee in accordance with democratic procedures'. This is the basis for what is on offer from Beijing today. China didn't promise anything different.
Comment by politicians and the media should not distort these historical agreements, which are the foundation for Hong Kong's status as a sub-national region with a high degree of autonomy, not a country or sovereign territory.
Perhaps part of the issue for some in the UK is an underlying feeling of post-colonial guilt, the idea that the British government didn't put proper protection in place for the people of Hong Kong.
But as the demonstrations have once again showed, Hong Kong people are quite capable of standing up for themselves. The idea - which some in Hong Kong encourage - that the UK is somehow still responsible for their well-being sounds outdated.
Furthermore, we should not forget the substantial achievements in the UK's negotiations with China over the future of Hong Kong. To engineer a smooth transition of sovereignty in 1997, followed by the maintenance of Hong Kong's legal, judicial, financial, social and economic systems, was no small achievement. It has provided the basis for a vibrant and passionate society in Hong Kong. Implementation was never going to be easy, but 'one country, two systems' remains the best option by far.
Those outside Hong Kong have a legitimate right to comment. But they also have a responsibility to base those comments on accurate and historically-informed analysis of the complex and emotive issues currently disputed in Hong Kong.
This article was originally published on CNN.com.
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