President Obama is “chronically incapable” of military strategy and falls far short of his predecessor George W. Bush, according to one of Britain’s most senior military advisors.

Sir Hew Strachan, an advisor to the Chief of the Defense Staff, told The Daily Beast that the United States and Britain were guilty of total strategic failure in Iraq and Afghanistan, and Obama’s attempts to intervene on behalf of the Syrian rebels “has left them in a far worse position than they were before.”

The extraordinary critique by a leading advisor to the United States’ closest military ally comes days after Obama was undermined by the former Defense Secretary Robert Gates, who questioned the President’s foreign policy decisions and claimed he was deeply suspicious of the military.

Strachan, a current member of the Chief of the Defense Staff’s Strategic Advisory Panel, cited the “crazy” handling of the Syrian crisis as the most egregious example of a fundamental collapse in military planning that began in the aftermath of 9/11. “If anything it’s gone backwards instead of forwards, Obama seems to be almost chronically incapable of doing this. Bush may have had totally fanciful political objectives in terms of trying to fight a global War on Terror, which was inherently astrategic, but at least he had a clear sense of what he wanted to do in the world. Obama has no sense of what he wants to do in the world,” he said.

The dithering over intervention against President Bashar al-Assad has empowered the Syrian ruler, undermined America’s military reputation and destabilized the Middle East, said Strachan. “What he’s done in talking about Red Lines in relation to Syria has actually devalued the deterrent effect of American military capability and it seems to me that creates an unstable situation, because if he were act it would surprise everybody,” he said. “I think the other issue is that in starting and stopping with Assad, he’s left those who might be his natural allies in Syria with nowhere to go. He’s increased the likelihood that if there is a change of regime in Syria that it will be an Islamic fundamentalist one.”

Britain’s shock parliamentary vote against military action in Syria also exposed Prime Minister David Cameron’s lack of a clear strategy. “It absolutely illustrated the failure to think through the strategic implications of his own actions,” said Strachan.

Strachan’s book The Direction of War, which will be published next month, examines the failure of modern political leaders to use strategy to predict and account for the implications of military action. Oxford University’s Professor of the History of War says the lessons learned at the end of the 2oth century proved to be damaging at the start of the next. “Using war did deliver. The wars were pretty short, the Falklands, First Gulf War, Kosovo, so people lulled themselves into an expectation that war was simply a continuation of policy and that it was successful. But it hasn’t been since 9/11,” he said.

Part of the problem, Strachan contends, is that politicians are unduly worried about allowing military leaders to give frank and open advice. He criticized the way General Stanley McCrystal was forced to resign after making unflattering remarks about his political bosses in Washington. “The concern about the military speaking out shows a lack of democratic and political maturity. We’re not facing the danger of a military coup. The professional experts, who deal with war all the time, should be able to express their views all the time, openly and coherently, just as you would expect a doctor or a teacher to express their views coherently about how you run medical policy or teaching policy,” he said.

Winston Churchill held daily strategy meetings with his chairman of the Chiefs of Staff during the Second World War, which encouraged an open exchange of views. “The Churchill-Allan Brooke relationship was fraught at times but it worked because both were pretty frank with each other,” Strachan said. “Soldiers have a duty here as well—if they just say, ‘yes Mr. Prime Minister or Mr. President, we can give you exactly what you want,’ then they’re probably not being very honest.”