Dean Acheson remarked in the 1950s that Britain lost an empire and had not yet found a role. For the next half-century, it found a niche as America’s global lieutenant — harnessing its influence in Washington to punch above its weight elsewhere. Events in Crimea over the past three weeks have underlined how fast even that is fading. Once America’s “go-to” ally, the United Kingdom is not even third on today’s priority list. When it comes to handling Vladimir Putin, Germany, France and even Poland rank ahead of David Cameron’s government in Washington.

The most visible change is in the shrinking size of UK defence spending. The US may be cutting the size of its army, but it still has almost 600,000 in uniform. At 102,000, the British army is far smaller than the US marine corps. And it is set to fall to just 82,000 next year, which is barely larger than America’s Special Forces. Following the principle of having three personnel at home to one in the field, this means Britain can only sustain 20,000 soldiers on the battlefront for a short period of time. For longer deployments, such as Afghanistan, 10,000 will be the limit. If the best the UK can do is to police Helmand province in Afghanistan or Basra in Iraq — and even then, not very well — its influence in Washington is unlikely to recover.

The same applies to the UK’s depleting military hardware. For the first time since inventing the aircraft carrier, the UK now deploys a grand total of zero. That is supposed to jump back up to two by 2019, but no one in the Pentagon is counting on it. Next year, the UK’s strategic defence review coincides with its general election.

The British have nothing like the attachment to their military as Americans. The days of outsized UK military clout in the US look numbered. “In terms of the UK-US defence relationship we are at the tail-end of a comet,” says General Jim Mattis, the former head of US central command.

Defence budgets can rise again. And the UK remains a great power in terms of its intelligence capabilities, but boasting about the close relationship between Washington’s National Security Agency and the UK’s Government Communications Headquarters is hardly a good idea nowadays. Countries such as Germany view the UK as an extension of America’s surveillance state. To the extent this further alienates continental Europe from the UK, it also undercuts the latter’s clout in Washington. Under Margaret Thatcher, Britain helped shape — and even drive — the European Union’s (EU) economic integration. Under Cameron, it prefers to carp from the sidelines. Last year, Phil Gordon, President Barack Obama’s adviser on Europe, caused a fracas in the UK by saying it was in America’s interest to see Britain strongly participating in the EU. He was right then and would be even more so today. Alas, Cameron pushed ahead with plans to hold an in/out referendum in 2017, if his Conservative party was elected.

Until recently, Americans have paid little attention to September’s Scottish referendum on independence from the UK. Those who have believed the Scots will probably decide against it. That remains to be seen: Scottish nationalists still have five months to change the poll numbers. However, America’s sense of a timeless Britain anchored firmly in its own identity is no longer taken for granted. From a distance, the UK’s destiny is starting to look wobbly. Can you depend on a “special relationship” with an ally that is no longer sure of who it is?

All this may be irrelevant to most British people — and even welcome. The wars in Iraq and Afghanistan were always unpopular. And cutting defence budgets is far more in tune with British sensibility than, say, taking the axe to the National Health Service. Moreover, the UK’s diplomatic service still punches above its weight. The embassy in Washington is among the most respected in town.

Yet, the UK is suffering from a growing reputational problem that threatens to undercut its still considerable soft power. In a recent piece in the New York Times, the author Ben Judah described London as the centre of Russian money laundering. “Any moralising remnant of the British empire is gone,” he wrote. “It has turned back to the pirate England of Sir Walter Raleigh.”

The argument would have sat comfortably in any British tabloid. But it drew on a strong underlying truth. Britain’s reluctance to impose tough sanctions on Russia is probably as much to do with BP’s large joint venture in Siberia — and the dividends it pays out — as from diplomatic calculation. Cameron’s disastrous recent visit to China was also noticed in the US. It reinforced the view that Britain’s worldview — like its defence budget — now resembles most of continental Europe. “Who would have thought that a British prime minister would go to China with no agenda other than selling things?” said one US official.

Then there is Tony Blair. The UK’s former prime minister used to be revered in the US for his lofty moralisms. People were also seduced by his charisma. Now he is better known for tawdry salesmanship. Former US presidents tend to fade from view, such as George W. Bush, or promote good causes, such as Jimmy Carter. Blair is out to make money — and lots of it. There would be an outcry if Bush took millions of dollars from Kuwait to advise it on “democracy”. When Blair does it, people just shrug. Alas, where Blair goes, the flag now seems to follow.

— Financial Times