Interesting thought, although most barley in the USA is grown north of the main drought areas. It's useless for the big vampire on corn production: ethanol for gasoline. Several groups are already lobbying in DC for the suspension of the EPA requirement for this year and that would go a long way to alleviate shortages.
Note: corn ethanol accounted for 40% of the 2011 corn crop and the EPA has mandated an increase to 15% in the blend.