In 1939, Winston Churchill colourfully described Russia as being "like a riddle wrapped up in an enigma". And, when one looks at the performance of President Donald Trump, that same description springs to mind. Does anyone really understand this American president and his actions? Does he even understand what he is doing?
His latest decision - to end the American side of the Iran nuclear deal - is a prime example of a bizarre and irrational foreign policy decision by Trump, fuelled, in part, by a loathing of former President Barack Obama.
The Iran deal was a multilateral agreement by Iran with the UK, France, Germany, Russia, China and the US to curb the Iranian nuclear development programme and end the undoubted danger of Iran developing nuclear weapons.
The Iranians agreed to the deal after many months of painstaking negotiations in exchange for extensive economic sanctions being lifted by the West, including the United States of America.
The sanctions were extensive and were crippling Iran's economy and its capacity to trade freely in the international market. The lifting of the sanctions has now given Iran the capacity to rebuild its trading links with the rest of the world.
While there was much opposition in the US to President Obama's support for the deal in 2015, there was equally fierce opposition to the deal within Iran itself.
Hardline elements within Iran's political establishment were strongly opposed to any such deal, especially with the US, which they hated and described as "the Great Satan". But the moderate Iranian president, Hassan Rouhani, persuaded the Iranians to accept it and signed up to the deal.
The unilateral ending of the deal by the US President, though not unexpected, has nonetheless sent shockwaves throughout the world. Many thought that Trump was simply engaging in electoral rhetoric, which would be abandoned soon after his election.
But this was not to be and Trump, sadly true to his word, has withdrawn America from an agreement which he has described as the "worst deal ever".
The medium-term consequences of his decision remain to be seen, but many fear that they will be profoundly negative.
The decision has immediately infuriated Iran and threatens to further destabilise an already unsettled political and military situation in the Middle East.
It has also undermined the authority of moderate President Rouhani, who persuaded the Iranians to accept the deal in the first place.
His critics have mocked his misplaced trust in the Americans. They have also called for a revocation of the deal by Iran as well.
Trump's decision was made despite the fact that the International Atomic Energy Authority had certified, this February, that the Iranian government was fully compliant with the terms of the deal. Mike Pompeo, the new US Secretary of State, also agreed that the Iranians were compliant.
Even allowing for Trump's apparent hatred for former Democrat President Obama, the decision does not make any political, military, or economic sense. The reality is that the nuclear agreement was working well and it had reduced the risk of an arms race in the Middle East.
Trump's decision achieves nothing tangible for America, or the world. It simply demonstrates to those hostile to the US and its interests that the Americans are not to be trusted and that they do not honour agreements.
This will surely sow seeds of distrust for any future deal that the Americans might hope to make with other countries - not least North Korea.
It unfortunately strengthens the perception - particularly among Arabs - that the US is in the pocket of the Israeli Prime Minister, Benjamin Netanyahu. For it was he, above all, who campaigned against the Iranian deal before it was signed and consistently afterwards.
The bitter irony of all this is that Israel is the only country in the Middle East that actually has nuclear weapons, even though it still denies that it has them.
Netanyahu's government is a coalition of hawkish nationalist parties, who have adopted a hardline stance on most issues.
We tragically witnessed that approach on Monday in Gaza, where there was a mass shooting of 57 Palestinian demonstrators by the Israeli army, gravely escalating an already very dangerous situation.
So, alongside the ending of the Iran deal, the provocative decision by Trump to relocate the US embassy from Tel Aviv to Jerusalem has destroyed relations between the Israelis and the Palestinians.
This unilateral decision is at odds with the international diplomatic consensus that sees Jerusalem's future as yet to be determined; as a "final status" issue within the context of a comprehensive peace.
While fulfilling an election promise may be one explanation for the irrational ending of a productive agreement with Iran, it is puzzling as to why Trump is so keen to end an agreement which all of the Western countries agree was a good deal and was being complied with by Iran over the past two years.