The first hydrogen bomb test, Ivy Mike, was detonated on Eugelab island of Eniwetok atoll. The device, called the Sausage, was purely experimental and far too big and heavy to be deliverable by any bomber; at 80 feet tall, 20 feet in diameter, with 2 foot thick steel walls. The explosion completely erased Eugelab, leaving in its place an underwater crater.
US
It had been in reasearch since the 1930's and the arms race began well before the 1950's. Neither the US or Russia wanted the other to have the weapon first so both were working on it.The Soviet 1953 "hydrogen bomb" was not a staged hydrogen bomb like the US 1952 & 1954 hydrogen bombs. It was just a Lithium Deuteride boosted fission bomb. Its only advantage was it was a deliverable megaton range yield boosted fission bomb one year before the US got deliverable multimegaton range yield teller-ulam staged fusion bombs.The Soviets only declared it a "type of hydrogen bomb" because some of the yield was from fusion, most was still from Plutonium fission. The design was sometimes referred to as the Layer Cake as it used a more or less conventional Plutonium implosion mechanism, but the Plutonium core was alternately layered with concentric shells of Lithium Deuteride instead of being just Plutonium.The US had considered such a design in ~ 1950, but never pursued it as it was considered a dead end. Computing resources were better spent on better designs.
Stan Ulam & Edward Teller had invented a mechanism based on Radiation Implosion that finally made one practical in early 1950.The USSR tested their first atomic bomb in 1949.The start of the Korean war in 1950.McCarthyism & the Red Scare.
A neutron bomb is a type of hydrogen bomb. It actually was a development that came from the late 1950s work by the US to make "clean hydrogen bombs" that produced very little fallout. In a conventional hydrogen bomb the tamper (device to contain the nuclear reaction as long as possible to get as much energy from it as possible) is usually made with depleted uranium because of its high density and low cost. While depleted uranium will not support a neutron chain reaction it will fission when hit by the high energy neutrons produced by the fusion reaction of the hydrogen bomb. This depleted uranium fast fission can produce up to 90% of the total yield in some hydrogen bomb designs, as well as a proportional amount of the fallout. In a "clean hydrogen bomb" the tamper is instead made of some other very dense metal that unlike uranium will not fission when hit by high energy neutrons. Lead and tungsten have been used. However the explosive yield of a "clean hydrogen bomb" will be lower than a similar conventional hydrogen bomb because there is no fission in the tamper. But as these materials do not consume the high energy neutrons, they escape from "clean hydrogen bombs". It was observed that these neutrons easily pass through tank armor and building walls, killing those inside while the lower yield produces less blast and fire damage. Thus was born the idea of the neutron bomb.
The first US weapon utilizing laydown delivery was the Mark 15 bomb, and was the first "light weight" thermonuclear bomb. The Mark 7 bomb was delivered using the loft bombing, a similar technique to laydown, but laydown delivery and lob delivery are not one-and-the-same for various reasons including the use of a retarding parachute on the bomb during laydown, and the attitude of the aircraft when the weapon is released.
that we knew how to build one
1952
No.However the first US hydrogen bomb test Ivy Mikecompletely destroyed an island (Eugelab in Enewetak Atoll), turning it into a crater.
1949 thru 1950 prompted by USSR atomic bomb test.
The hydrogen bomb.
Some 43 nuclear tests were detonated at Enewetak from 1948 to 1958. The first hydrogen bomb test, code-named Mike, was tested on November 1, 1952. The explosion vaporized the island of Elugelab. This was done for testing.
US
They did test the bomb first, in 1945 at the White Sands Proving Grounds near Socorro, New Mexico.
The first hydrogen bomb tested by the US was codenamed "Mike" and tested in the Marshall Islands.
Yes, both.
atomic bomb or the hydrogen bomb
The island of Eugelab in Eniwetok atoll ceased to exist.