Israeli Prime Minister Benjamin Netanyahu claims Iran will not pursue nuclear weapons following U.S. and Israeli strikes, stating Tehran is afraid after feeling "the might of America and Israel."

How difficult is it in 2025 - 80 years after the Manhattan Project - for a nation to build a nuclear weapon? To find out, McClatchy News spoke with six nuclear proliferation experts. They described the process of constructing an atomic weapon as a complex operation that requires three major stages - some of which are substantially more challenging than others.