Hailed as a jump-start for the U.S. economy, the federal government's "cash for clunkers" gave the biggest boost to foreign automakers. Overall, auto sales in August were the highest in more than a year, according to industry figures released Tuesday. Carmakers sold more than 1.2 million cars and trucks, up 1% from the same month last year and the first year-over-year sales gain since August 2007. Much of that was a result of the clunkers program, which ran July 24 to Aug. 24 and provided hefty government rebates to consumers who traded in gas guzzlers for more fuel-efficient new vehicles....