Nuclear weapons

The spreading of the nuclear weapon can maintain the peace of the world. Mightier countries uses their power to subject humiliate an dot spread their influence over smaller countries. So in reality, USA attacked countries such as Vietnam, Iran, Afghanistan, and USSR attacked Afghanistan, and Georgia. This happened because there was no balance in the powers between a nuclear country and non nuclear one. If these countries had nuclear power, would they get still even though they get attacks? They might've attacked the US and the USSR. However, since they didn't have the nuclear weapon and that there aren't balances in the power with the big countries, they can't. In comparison, however when the country has a nuclear weapon, the peace can be maintained. As an example, In the cold war, it was very difficult to keep the world peace. Sometimes, there were possibility of world war 3. However, the peace was maintained because of the balance in power. US and USSR both possessed nuclear weapons and they both knew that if one of them uses a nuclear weapon a mass destruction would have occurred. Isn't it surprising that the nuclear power was used for keeping peace? Many people have prejudice that the nuclear power ruins the world peace, however, it can prevent the mass killing from the fear from each other. Thus, all countries should have the right to possess nuclear weapons.