Editor's note: Jonathan Arnott is a former member of the European Parliament. The article reflects the author's views, and not necessarily those of CGTN.

In order to understand the British government's mindset towards Hong Kong, let me take you back almost four decades to the early 1980s. The United Kingdom had gone to war over the Falkland Islands, or Malvinas Islands, in 1982. Buoyed by a military victory and the green shoots of economic recovery, Prime Minister Margaret Thatcher was re-elected the following year with an increased majority. 

When it came to Hong Kong, the British government found itself in a quandary over two issues (sovereignty and immigration) which have, coincidentally, both come back to the fore in recent years in a very different context. Thatcher knew that she had a problem: if her actions led to sudden, large-scale immigration to the United Kingdom from Hong Kong, she feared a backlash within her own party. Yet if she were to agree to hand Hong Kong back to China without concessions, she would face serious questions about how she perceived sovereignty – especially after going to so much trouble to defend the Falkland Islands, and British soldiers having died. The timing of discussions could not have been worse.

Meanwhile, the decision could not be put off much longer after discussions between the UK and China had continued for years. The UK's lease of the New Territories, which are geographically the largest part of Hong Kong, was due to expire in 1997. The remaining land would have, in the UK government's view, been too small to be manageable – and China was in any case staking its claim for sovereignty.

A secret UK government document warned Thatcher "what she could not do, particularly in the light of the recent Falkland Islands problem, was simply to announce that we had conceded sovereignty over Hong Kong." After long negotiations, the two sides agreed to a compromise: the "One Country, Two Systems" principle that would leave Hong Kong's governance unique under its "Basic Law" but falling under China's sovereign control. China regained the whole of the territory; the United Kingdom received assurances in return that Hong Kong would continue with a degree of autonomy until 2047. Even so, there was some disquiet towards Margaret Thatcher from within her own party.

Today, almost 66 years later, the British government sees China's national security legislation for Hong Kong as putting this compromise to the test. Boris Johnson, the most Thatcherite prime minister since Thatcher herself, is predisposed to push back. Yet there is no obvious diplomatic means of doing so. He speaks of creating the right of immigration from Hong Kong to the United Kingdom.

China could perceive any such decision in two ways. It could see such a decision as provocation and political interference, or as creating a practical pressure valve which could de-escalate tensions.

Johnson does not need to make his decision yet. His opinion piece for the South China Morning Post reads like the words of a prime minister who intends to adopt a "wait and see" approach.

From Johnson's own political perspective, it is probably the best move. He enjoys a large majority in Parliament, but is already facing battles on multiple fronts – not least his government's handling of the COVID-19 outbreak and the ongoing future trade relations with the European Union.

Like Thatcher did three decades ago, Johnson has his own timing problem. There is a small but growing narrative in the UK seeking to blame the Chinese government over its early response to the COVID-19 virus. For this reason, the pressure from within his own Party to reverse his position on Huawei's involvement in the UK's 5G network is growing.

The British government is seeking to cultivate a particular image of itself: keen to attract new skills and talent from overseas, whilst reducing immigration rates as a whole. Allowing long-term immigration from Hong Kong would be a double-edged sword for Johnson – likely perceived as doing the former, at the expense of the latter.

As ever in politics, the British government is walking a tightrope. At his core, Johnson is more of an internationalist than he appears, yet he is well aware of strongly anti-China factions within his own party. Therefore, for the time being, he is likely to wait. To Johnson, the litmus test will be whether (and how) the new law is used within Hong Kong.

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