The addition of John Bolton, the former US national security adviser, to the long list of distinguished American foreign policy experts who have lost their jobs during Donald Trump’s presidency demonstrates that, for all his lack of experience in the world of foreign diplomacy, the American president is not a man to be trifled with.
Prior to Mr Bolton's precipitate departure from the White House earlier this week, the Trump administration had presided over a steady stream of high-profile national security officials leaving their jobs, including former defence secretary James Mattis and Mr Bolton's immediate predecessor, HR McMaster.
In each case the departures have occurred because sharp differences of opinion have emerged between the president and his key advisers over the direction of American policy.
In both instances one of the reasons given for the breakdown in relations between both Mr Mattis and Mr McMaster and the Oval Office was their more robust approach to national security issues, especially American policy towards Afghanistan.
Having held senior command positions during America’s long-running military engagement in Afghanistan in the wake of the September 11 attacks in 2001, both men felt strongly that America should continue to support the democratically elected Afghan government in its continuing battle against the Taliban and other Islamist terror groups such as ISIS that are operating in the country.
They were firmly of the view that, after the loss of more than 4,000 American lives in Afghanistan and a military campaign that has cost an estimated $1 trillion, it was very much in America’s national interest to ensure that, following the withdrawal of the bulk of US troops at the end of 2014, the country did not once again fall into the hands of the Taliban and become a safe haven for Islamist terror groups to plot attacks against the West.
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Mr Bolton, whose involvement in the Afghan issue dates back at least to the Bush administration, had a similar outlook on the issue. His preference was for maintaining a significant American military presence – the number of US forces currently based in the country stands at around 15,000 – in support of the government of Afghan President Ashraf Ghani.
Afghanistan’s fledgling democracy is, after all, one of the few tangible gains of the US-led military intervention in the country, one that allows ordinary Afghans a say in the way their country is governed for the first time in their history. And, as a prominent supporter of the neo-conservative movement, which campaigns for the introduction of Western-style democracy in countries with no tradition of democratic rule, Mr Bolton was committed to supporting the Afghan government.
The other important national security consideration from Washington’s point of view is that sustaining a democratically elected government in power in Kabul is the best way of preventing the country from being overrun by Islamist terror groups.
The problem for Mr Bolton, as well as other distinguished US national security experts like Mr Mattis and Mr McMaster, is that their desire to maintain support for the Afghan government was at odds with Mr Trump’s desire to end America’s involvement in costly and politically damaging overseas military adventures.
Mr Trump’s preferred outcome, so far as Washington’s involvement in Afghanistan is concerned, is to negotiate a deal that ends the country’s long-running civil war, one that allows remaining American forces in the country to return home – preferably in time for next year’s presidential election contest.
And it is to this end that Mr Trump has encouraged Zalmay Khalidzad, the Afghan-born US diplomat, to engage in talks with the Taliban aimed at ending the conflict.
Indeed, such was the president’s enthusiasm for the process that he even decided to invite a group of Taliban leaders to Camp David earlier this week in the hope of securing a deal.
There is nothing Mr Trump likes more than doing a deal. The primary motivation for his face-to-face meetings with North Korean dictator Kim Jong-un is to negotiate a deal that would end the decades-long stand-off between Washington and Pyongyang over North Korea's nuclear programme.
Mr Trump has adopted a similar approach to the Iran issue. It is often forgotten that when Mr Trump initially signalled his intention to withdraw from the Iran nuclear deal last year, his primary objective was to get a better deal with Tehran, one that covered other aspects of Iran's nuclear programme such as ballistic missiles, rather than provoking a military confrontation. And this still remains his primary objective, as demonstrated by his suggestion that he would like to meet with Iranian President Hassan Rouhani.
But the president’s love of a deal has often put him at loggerheads with hawkish foreign policy veterans such as Mr Bolton who believe adopting a more robust approach to rogue states such as North Korea and Iran is a better way of achieving results.
This was certainly Mr Bolton’s view with regard to the Taliban, a movement he continues to regard as a terrorist organisation.
And the notion that Mr Trump was prepared to entertain Taliban leaders at Camp David as America prepared to commemorate the 18th anniversary of the September 11 attacks was clearly too much for Mr Bolton, who is reported to have protested his opposition to the meeting taking place in the strongest possible terms.
In any event Mr Trump decided to cancel the meeting, not because of Mr Bolton’s objections, but because the Taliban claimed responsibility for carrying out a terrorist attack that claimed the life of an American soldier.
Nevertheless, Mr Bolton’s position became untenable, and the president demanded, and received, his resignation. Which only goes to show that, in any White House battle over the direction of American foreign policy, Mr Trump is always going to emerge victorious.
Con Coughlin is the Daily Telegraph’s defence and foreign affairs editor