Tens of thousands of protesters have braved blistering heat and then pouring rain this week to take to the streets of Hong Kong. Their mission: to secure democracy for a city of seven million people.

This is a city left behind. Ever since the former colony’s return to China, Hong Kong has been characterised as the last page of an era that belongs to the history books – the era of empire. Most Britons are ignorant of the fact that Britain – the signatory to the Sino-British Joint Declaration – remains legally liable to the implementation of the handover, including the protection of Hong Kong’s autonomy.

This is a people let down. When Margaret Thatcher bowed to Beijing 30 years ago, she expected Hong Kong to democratise and its way of life to stay the same. Yet Beijing has since crossed the red line consistently. The central government overrode Hong Kong’s judiciary by re-interpreting the Basic Law (the city’s constitution). It delayed universal suffrage. And most recently it published a White Paper intervening in political reform, an action The New York Times criticised as unprecedented, saying China ‘unambiguously asserted its complete jurisdiction over Hong Kong.’ There can be no greater breach of an international agreement than this.

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Insulted and ignored, Hong Kong might expect a powerful British response. Yet when Premier Li KeQiang shook the Queen’s hand two weeks ago, not a word was raised by David Cameron concerning violations of Hong Kong’s autonomy. The Prime Minister certainly did not heed The Independent’s Ben Chu’s advice, that with much of its cash locked in US debts and mortgages, “China needs Britain just as much as Britain needs China.” Instead, as cautious Cameron eyed the £14 billion of investment Li carried with him (which a Foreign Office minister jubilantly tweeted), Hong Kong was out of mind and out of sight. Money talks. Cameron dared not offend his guest of honour.

Meanwhile, on the other side of the world, things are moving fast. Over the past week, 700,000 people had stuck two fingers up to Beijing in an unofficial referendum, which China has declared ‘illegal’. The referendum was organised by pro-democracy Occupy Central, a group that advocates the occupation of the city’s financial district if the government puts forward political reforms short of full democracy. Tuesday’s march, an annual demonstration for democracy held on the handover anniversary, is just another example of the Hong Kong’s resilience in the face of China’s hegemony. This is as strong a signal a people can send for their desire for democracy.

Still, silence from the country that transferred seven million people to authoritarian China. The one Briton who (probably still) cares, Lord Chris Patten, the last governor of colonial Hong Kong, is now more associated with his troubled tenure as chairman of the BBC. Most British people would be shocked to see the footage of Hong Kongers waving colonial flags, with God Save the Queen in the background, and beseeching Lord Patten to please come back. Lord Patten described this as a ‘tint of nostalgia,’ and values such as the rule of law are ‘part of this city’s DNA.’

As a dual citizen of both Hong Kong and Britain, I cannot help but wonder why Britain acts as timidly as it currently does. Is this the same country that defended the people of Falklands in 1982? Is this not the country that wants a more democratic relationship with European Union here at home? Surely, the democratic deficit facing Hong Kong is more severe than that between Brussels and London. Even though Hong Kong is not threatened by an Argentine-style invasion (the People Liberation Army already stations in Hong Kong), the subtle subversion by China on Hong Kong’s liberty is no less dangerous and engulfing.

Nobody is suggesting the fanciful notion of return to British rule in Hong Kong. But it is definitely within our power to lend vocal support to democrats in Hong Kong (as the NYT editorial recommends), by expressing diplomatic concerns and placing the issue on the agenda of international affairs. It does not take an army, but it will take a strong stance, some wise words, plus principled and courageous leadership. A backbone, in short. Something lacking from this country’s political class at the moment.