See the chart below.
Nuclear armed nations are appearing, but only Big 5 have operational nuclear warheads.
Some proliferators like Iran and North Korea are not ready to fire warheads immediately. They claim nuclear power status, primarily for brinkmanship diplomacy and sponsoring terrorism. Senator Bob Casey testified “A nuclear Iran would feel empowered to conduct more terrorist attacks against U.S. and Israeli targets, provide more lethal assistance to Hezbollah and Palestinian militant groups, and give the Quds Force greater freedom to support terrorist groups across the Middle East,” at a Senate Foreign Relations subcommittee (“US Senators Examine Iranian Involvement with Terrorism”; VOA News; July 25, 2012). North Korea will act similarly to Japan, South Korea, and the United States.
Also, we have to note that lack of transparency with Chinese nuclear weapons. It is unknown how many warheads are operational for strategic and tactical use. Such a big power has not joined nuclear arms cut negotiations, and leaves the responsibility to the United States and Russia. Beijing Communist Party should disclose more information about their nuclear weapons.
