An old English proverb quoted by Henry Wadsworth Longfellow goes... ‘though the mills of God grind slowly, yet they grind exceeding small; though with patience he stands waiting, with exactness grinds he all’. In other words no matter how.

And so it was with US President Trump, who a week ago unsuccessfully attempted to stage an insurrection to overturn the US presidential election results in which he was the losing candidate. Slowly but surely the wheels of justice are closing in on him. 
Mr. Trump has now been impeached for a second time, and will soon be tried in the Senate. If convicted he will be next be prevented from contesting the presidency ever again.

He has also been banned by the social media giants -Twitter and Facebook- which provided him a huge international platform which he had used to promote his unsubstantiated false claims that the 2020 US presidential election results were rigged. The false propaganda led to thousands of his supporters heeding his call to storm the Capitol where the ratification of the election results was being certified.
 A humbling experience for most men, but Trump is not a humble man and this is not the future he would have planned for himself - going out like a whipped mongrel with his tail between his legs. 

Given his personality Trump needs to go out in a blaze of publicity. It is in this light that we must view the latest claim Trump’s Secretary of State Mike Pompeo made without proving any evidence; ‘Iran has given al-Qaeda a new home base’. The US and Iran have been locked in a battle for power and influence in the Gulf region. Because of its possession of natural resources, Iran has constantly suffered from foreign intervention. 
In 1953 for example, US and British intelligence agencies collaborated to organize a coup to remove Iran’s democratically elected Prime Minister, Mohammad Mossadeq.
Mossadeq sought to nationalize the Iranian oil industry, which was then controlled by Britain. The coup, reinstated the monarchy under the Western-friendly Shah, but eventually fueled a surge of nationalism which culminated in the 1979 Iranian Revolution.

Because of its size, natural resources, and strategic position, Iran has striven to assert its influence in the Persian Gulf region. The Islamic Republic has also chartered an independent course, often undermining American and western interests in the Gulf region.
As a result Iran finds itself isolated. Relations between the two nations (Iran and the US) completely broke down with the overthrow of the US-backed Shah, the setting up of the Islamic Republic, the takeover of the American embassy in Teheran and holding hostage US embassy staff by radical students who were in the forefront of the revolution.

The US swiftly imposed sanctions on Iran after the hostage crisis began, cutting off sales of Iranian oil, freezing Iranian assets closing Iranian institutions within the US and embargoing all imports from Iran.
In 2002, the United States learned Iran had been enriching uranium and was developing a nuclear programme. The US began freezing the assets of individuals and businesses it suspected of aiding Iran’s nuclear programme and tightening sanctions.  In 2015, President Obama announced a nuclear accord that lifted some sanctions in exchange for an end to Iran’s nuclear programme. However in 2018 President Trump announced he was withdrawing the US from its 2015 nuclear accord with Iran and re-imposing economic sanctions against the country.

In January 2020 Trump ordered the killing of Iran’s most powerful military commander -General Qasem Soleimani- marking a major escalation in the conflict. Iran retaliated by firing over 20 missiles at two military bases in Iraq that hosted US troops.  The Guardian reports, Pompeo’s claims (without any evidence), with days left in President Trumps term that Iran allowed al Qaeda, to establish a new operational  headquarters, is viewed with skepticism within the US intelligence community as well as among independent analysts.
However, Pompeo’s real objective appears to be providing Trump with an excuse to commence an attack on Iran, allowing him to leave the presidency with a last flourish.