. >> these countries are cheek and jowell, right next to each other. things could escalate quickly there. they don't have the same protocols and history that the u.s. and the soviet union did. >> north korea has conducted three nuclear tests raising tensions with neighboring south korea. i have been saying we are only one dead fisherman away from a small incident that could escalate quite quickly on the korean peninsula in which case you would you could have a war or nuclear weapons. >> nuclear experts say they are either expanding, upgrading or modernizing as naldz and that the global nuclear threat will grow in the coming years. leaders have struggled to con table nuclear weapons since they were invented. it was a concern for john f. kennedy more than 50 years ago. >> every man, woman and child lives under a nuclear sword of damaclese hanging on a thread, or by madness. the weapons of war must be abolished before they abolish us. >> today, at least eight countries have nuclear weapons and there are real fears terrorists could get a bomb. >> will be t