Is a tornado more violent going clockwise or counter-clock wise?

That depends on where the tornado is. Generally, tornadoes in the northern hemisphere rotate counterclockwise while those in the Southern Hemisphere rotate clockwise. There are more violent tornadoes in the horthern hemisphere, but that is mostly due to the fact that portions of the United States have an almost perfect setup for producing them. A small percentage of tornadoes rotate in the opposite direction from what is normal. These are called anticyclonic tornadoes (normal tornadoes are cyclonic). Many anticyclonic tornadoes are satellite tornadoes, and are generally weaker than the parent tornado that spawned them. Only one anticyclonic tornado has ever recieved a violent (F4 or F5) rating on the Fujita scale. It was an F4 that hit West Bend, Wisconsin on April 4, 1981.