As of November 4th 2013 there are 9 countries that possess nuclear weapons -- United States, Russia, France, United Kingdom, China, Pakistan, India, Israel, and North Korea. Depending on one's definition there are between 193 and 250 countries currently, which means approximately 3.7 to 4.7% have nuclear weapons.
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In the early 1960s, the U.S. was the world's dominant industrial power accounting for about 40.3 percent of world manufacturing output. By 2005 the United States accounted for only 20.1 percent
This is largely a matter of opinion as 'most powerful' is not easy to define. The following list is at least an approximation to a valid answer. People may argue over the relative status of these nations.The United States of America: The world's biggest economy and by far in terms of spending and power the worlds strongest army.Russian Federation: The second largest army. The largest European population, and largest world area, which gives it immense control over itself, and immense levels of independence . The size of Russia helps give it extra resources and abilities that make it such a big power.Peoples Republic of China: China has the largest standing army of any nation in the world, however the technology other nations bring to bear may occlude China's size.France: The fifth republic has UN security council membership, is a nuclear power and has alot of influence over Africa.The United Kingdom: UN security council status, nuclear weapons, and vast experience serving in nearly every nation (and certainly on ever continent) of the world.In terms of nuclear weapons, Russia has the the largest stockpile, (more than all the other nation's nuclear weapons combined), with the US having the second largest arsenal, but the most technologically advanced (more bang for the buck).
The first nuclear bomb was created by the United States in 1945. No one person invented it. It was developed under a secret effort named the Manhattan Project. The project was under the direction of a theoretical physicist named Robert Oppenheimer but Enrico Fermi and several other of the nation's top physicists lent their knowledge and ingenuity to the project. He is noted for saying when he saw the first nuclear explosion, words from the Bhagavad Gita came into his mind. "Now, I am become Death, the destroyer of worlds," .
After World War II there was a shift from isolationism to internationalism. The United States and most of the world looked to the principle of collective security to keep international peace. The United States took the lead in creating the United Nations in 1945. The principle of deterrence has been a basic part of American foreign policy since World War II. Toward the end of World War II, the United States had hoped to work with its wartime ally the Soviet Union, through the UN, to build international cooperation and to keep the peace in the postwar world. What was the cold war
none of the world wars were litterally a world war, not all of the countries fought on both wars and the countries didnt fight everyone on each other in both wars, WW2 was classified as a war world because it splitted most of it [Europe and USA joined it too] into 2 groups that fought each other: Allies and Axis.
nuclear weapons
With the creation of the worlds first nuclear weapons.
4-5%
france
About 16 percent, according to this website: http://www.world-nuclear.org/info/inf01.htm
The world's 70% of the energy comes from coal or fossil fuel based power, most of the countries currently use Nuclear as their leading power supply, one such example is France which produces 90% of its energy from Nuclear fuel
After inventing the nuclear weapon, Dr. Oppenheimer famously remarked, "Now I am become Death, the destroyer of worlds." This quote reflects the immense power and destructive potential of the atomic bomb.
Both these countries are a major leader.About 70 percent are made in China and Japan.
60 percent of the worlds hunger is from the Indian Subcontinent, and 40 percent is from Asia and Africa.
United States and Canada
Nuclear weapons were originally constructed for the purpose of; mass destruction, shock and as an ADM; Area Denial Munition. It was believed that whoever were the first to develop them would win World War II they were that powerful. Nowadays they are more useful in Mutually Assured Destruction; none have been fired in anger since WWII however with all the worlds superpowers having them it acts as a deterrent against war between these countries since the could annihilate each other by the press of a button.
Trinity