In his state of the union address in January 1952, President Harry Truman announced that the U.S. had successfully developed a hydrogen bomb.
A thermonuclear weapon, fusion weapon or hydrogen bomb (H bomb), is a second-generation nuclear weapon design. Its greater sophistication affords it vastly greater destructive power than first-generation atomic bombs, a more compact size, a lower mass or a combination of these benefits. Characteristics of nuclear fusion reactions make possible the use of non-fissile depleted uranium as the weapon’s main fuel, thus allowing more efficient use of scarce fissile material such as uranium-235(235U) or plutonium-239
Modern fusion weapons consist essentially of two main components: a nuclear fission primary stage (fueled by 235U or 239Pu) and a separate nuclear fusion secondary stage containing thermonuclear fuel: the heavy hydrogen isotopes deuterium and tritium, or in modern weapons lithium deuteride. For this reason, thermonuclear weapons are often colloquially called hydrogen bombs or H-bombs.