The United States has conducted 1,127 nuclear and thermonuclear tests — 217 in the atmosphere.
The Soviet Union/ Russia conducted 969 tests — 219 in the atmosphere.
France, 210 tests, 50 in the atmosphere.
The United Kingdom, 45 tests — 21 in the atmosphere.
China, 45 tests — 23 in the atmosphere.
India and Pakistan — 13 tests underground.
Israel — possible 1 test atmosphere South Africa 1979.
North Korea — 1 test underground, October 2006.
"The United States is now involved in a massive program to overhaul its nuclear arsenal. In fact they're working to replace every nuclear warhead and all of the existing delivery systems in the arsenal to ensure prompt precision global strike capabilities.”