A top British defense adviser has called President Barack Obama “chronically incapable” of implementing a successful military strategy in Syria and Afghanistan, and has "no sense of what he wants to do in the world."

Sir Hew Strachan, a member of the United Kingdom’s Chief of the Defense Staff’s Strategic Advisory Panel, told The Daily Beast Wednesday that Obama's handling of the Syrian crisis was "crazy" and, as the publication put it, perhaps “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," Strachan said. "[Former President George W.] 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 added.

With his comments, Strachan joins a growing chorus of criticism directed at the president's handling of U.S. military affairs from former and present U.S. officials.

In a recently released memoir, for example, former U.S. Defense Secretary Robert Gates called Obama’s decision to declare a “red line” on Syria’s use of chemical weapons a “serious mistake.”

Those sentiments were previously echoed by Adam Smith, the top Democrat on the House Armed Services Committee, as well as former Connecticut Independent Sen. Joe Lieberman, both of whom suggested the president’s red line assertion would draw U.S. forces into another foreign war.

"You do not say, 'If you step across this line, we will commit U.S. military force,' unless you really mean it, unless you know the full implications of it," Smith told the Council on Foreign Relations in November, according to The Washington Post.

Lieberman also told the Homeland Security Committee this week the president has "no coherent" anti-terrorism strategy to combat al-Qaida’s growing influence.

"If we don't do something more than we're doing now, they're going to tip over," Lieberman predicted, referring to Syria, Iraq and Libya, where al-Qaida is gaining traction.

If that happens, "we're going to get attacked again," he added, according to the Associated Press.

Shortly after the president’s 2012 red line declaration, Syria launched a chemical weapons attack and Obama moved U.S. war ships into the eastern Mediterranean Sea without seeking support from Congress.

Moves such as that “undermined America’s military reputation and destabilized the Middle East,” Strachan said.

“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 (to) act it would surprise everybody.”

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