So do you think that America is cursed and if so why.
"Cursed" would, to me, imply that there is some external supernatural agent affecting what happens. If the climate or weather patterns of a particular part of the USA causes many more tornadoes than elsewhere, then that's the cause. No other agent is necessary. In the same way that places that sit on fault lines will experience more (and/or more severe) earthquakes than other places. And so on.
Our minds can be described as "pattern seeking missiles." We absolutely hate
not knowing the why and how of anything, and if we cannot find it through research and study, we reach for anything else available. You will see this whenever there is a tragic occurrence. I can recall the insistence from some corners that the Columbine shootings were the result of violent video games. And I understand that Pat Robertson has blamed the recent tornadoes in Oklahoma on a lack of prayer. Although that latter is less because it satisfies a need for answers and more because Pat Robertson is a repulsive opportunist and vile human being.
In any case, I don't believe in curses. I believe that we identify patterns where there are none and call them curses, or lack of prayer, or whatever gives us the answer we want.