There was a time when growing hostilities between two superpowers; America and Russia was said to be one of the reasons which could have started World War III. However, that crisis is now over. Though these two nations are quite hostile against each other and have the biggest arsenal of nuclear weapons, still experts are of the opinion that they don't have any reason in hand to go into war with each other.
However, the chances of World War III still exist. According to some experts, slightest of tension between India and Pakistan, two neighbouring countries can spark a war. And if these two countries get involved in an all-out war, then we have World War III on the table. One of the main reasons, which has been pointed out as a Nuclear Flashpoint by former Pakistani Prime Minister Mr. Nawaz Sharif is Kashmir. Kashmir, according to Pakistan is an unresolved issue of partition and they claim Kashmir to be a part of Pakistan. Post-1947, India and Pakistan have been at war on 4 occasions, out of which 3 was triggered by the Kashmir issue. The reason why a war between India and Pakistan can lead to a World War is because it would draw other allies of these countries into the war as well. China, USA, Russia, Israel, France are some of the countries who won’t be able to hold themselves back.