Guardian: America’s gas guzzling automobile was heading towards extinction today as Barack Obama set strict limits on car exhaust emissions, and directed producers to make a more fuel-efficient vehicle fleet. The new policy requires US automakers to produce cars and trucks that get an average 35.5mpg by 2016, and will reduce America’s carbon dioxide emissions by 30%. It marks the end of the line for the SUVs and luxury cars that were best sellers in a country where consumers see low …