Whats going to happen if Greeks don't get their debt crisis under control? Is the USA and world doomed?BELOW!!?

I live in America, and watched Gerlad Celente talk about the Greek debt crisis be the betrue beginning of the end for the world financial system. HE said that once Greece defaults, our economy dies with it, plunging us into a forever depression. I'm scared ebcause I have sick family memeber who need their jobs and insurance benefits with it i order to keep getting treatment....AND I DON'T WANNA SEE PEOPLE EAT EACHOTHER BECAUSE NO ONE CAN AFFORD FOOD. Pat RObetson even said this will destroy us when they default, because we die with them, and that because the bee population is dying off as well, theres alreayd gonna be mor expensive and less food. I DON'T WANNA DIE HELP!!!!!!!!!