Crude oil prices began trade this week with a gain following the news that Islamist rebel groups had ousted Syria’s President Bashar Assad and taken over the country in a blitzkrieg-style offensive that lasted less than a month. At the time of writing, Brent crude was trading at $71.54 per barrel, with West Texas Intermediate at $67.63 per barrel. The price gains were limited as pessimism about demand growth remained strong. “The development in Syria has added a new layer of political uncertainty in the Middle East, providing some support…