test for a first-class power is whether it has made an atomic bomb and we have either got to pass the test or suffer a serious loss of prestige both inside this country and internationally." Although the British government had committed to the development of an independent nuclear deterrent, it still hoped for a restoration of the nuclear Special Relationship with the Americans. It was therefore important that nothing be done that would jeopardise this. Site selection Implicit in the decision to develop atomic bombs was the need to test them. Lacking open, thinly-populated areas, British officials considered locations overseas. The preferred site was the American Pacific Proving Grounds. A request to use it was sent to the American Joint Chiefs of Staff in 1949. In October 1950 the Americans turned down the request. As a fallback, sites in Canada and Australia were considered. Penney spoke to Omond Solandt, the chairman of the Canadian Defence Research Board, and they arranged for a joint feasibility study. The study noted several requirements for a test area: an isolated area with no human habitation downwind; large enough to accommodate a dozen detonations over a period of several years; with prevailing winds that would blow fallout out to sea but away from shipping lanes; a temporary camp site at least upwind of the detonation area; a base camp site at least upwind of the detonation area, with room for laboratories, workshops and signals equipment; ready for use by mid-1952. The first test would probably be a ground burst, but consideration was also given to an explosion in a ship to measure the effect of a ship-borne atomic bomb on a major port. Such data would complement that obtained about an underwater explosion by the American Operation Crossroads nuclear test in 1946, and would therefore be of value to the Americans. Seven Canadian sites were assessed, the most promising being Churchill, Manitoba, but the waters were too shallow to allow ships to approach close to shore. In September 1950, the Admiralty suggested that the uninhabited Montebello Islands in Australia might be suitable, so Attlee obtained permission from the Prime Minister of Australia, Robert Menzies, to send a survey party to look at the islands, which are about and from Onslow. Major General James Cassels, the Chief Liaison Officer with the United Kingdom Services Liaison Staff (UKSLS) in Melbourne, was designated the principal British contact in