GE Dish Washer arms not rotating

[LEFT]I ran my GE to clean dishes and did not do that. It seemed like the lower rack was clean somewhat but top rack was still dirty. Used a cascade complete but that was still in detergent cup. Inspected while door was open the lower arm was spraying water but it did not seem with alot of pressure and did not rotate. Upper arm was not even getting water. Could this be the pump?[/LEFT]