Editing Convoy (section)

====Atlantic====
{{see also|Battle of the Atlantic}}
[[File:Convoy routes 1941.jpg|thumb|Convoy routes in the Atlantic Ocean during 1941]]
[[File:Allied convoy underway in the Atlantic Ocean near Iceland, circa in 1942 (80-G-72409).jpg|thumb|Allied convoy near Iceland, 1942]]
[[File:Convoy in Bedford Basin, Nova Scotia Convoi dans le bassin de Bedford (Nouvelle Écosse) (8640015819).jpg|thumb|Allied convoy in [[Bedford Basin]], Nova Scotia on 1 April 1943]]
The British adopted a convoy system, initially voluntary and later compulsory for almost all merchant ships, the moment that [[World War II]] was declared. Each convoy consisted of between 30 and 70 mostly unarmed merchant ships.<ref>[http://www.history.ca/ontv/titledetails.aspx?titleid=248473 Convoy] {{webarchive|url=https://web.archive.org/web/20110719201429/http://www.history.ca/ontv/titledetails.aspx?titleid=248473 |date=2011-07-19 }} from ''History Television.''</ref> Canadian, and later American, supplies were vital for Britain to continue its war effort. The course of the [[Battle of the Atlantic]] was a long struggle as the Germans developed anti-convoy tactics and the British developed counter-tactics to thwart the Germans.

The capability of a heavily armed warship against a convoy was dramatically illustrated by the fate of [[Convoy HX 84]]. On November 5, 1940, the German heavy cruiser {{ship|German cruiser|Admiral Scheer||2}} encountered the convoy. ''Maiden'', ''Trewellard'', and ''Kenbame Head'' were quickly destroyed, and  ''Beaverford'' and ''Fresno City'' falling afterwards. Only the sacrifices of the [[Armed Merchant Cruiser|armed merchant cruiser]] {{HMS|Jervis Bay|F40|6}} and the freighter ''Beaverford'' to stall the ''Scheer'', in addition to failing light, allowed the rest of the convoy to escape.

The deterrence value of a battleship in protecting a convoy was also dramatically illustrated when the German light battleships (referred by some as battlecruisers) {{ship|German battleship|Scharnhorst||2}} and {{ship|German battleship|Gneisenau||2}}, mounting {{convert|11|in|cm|abbr=on}} guns, came upon an eastbound British convoy ([[Convoy HX 106|HX 106]], with 41 ships) in the North Atlantic on February 8, 1941. When the Germans detected the slow but well-protected battleship {{HMS|Ramillies|07|6}} escorting the convoy, they fled the scene rather than risk damage from her {{convert|15|in|cm|abbr=on}} guns.

The enormous number of vessels involved and the frequency of engagements meant that statistical techniques could be applied to evaluate tactics: an early use of [[operational research]] in war.

Prior to overt participation in World War II, the US was actively engaged in convoys with the British in the North Atlantic Ocean, primarily supporting British activities in Iceland.<ref>{{Cite book|title=The Western Hemisphere, Guarding the United States and Its Outposts|last=Conn|first=Stetson|publisher=Office of the Chief of Military History, Department of the Army. US Government Printing Office|year=1964|location=Washington, D.C.|pages=470}}</ref>

After Germany declared war on the US, the US Navy decided not to organize convoys on the American eastern seaboard. US Fleet Admiral [[Ernest King]] ignored advice on this subject from the British, as he had formed a poor opinion of the Royal Navy early in his career. The result was what the U-boat crews called their [[Second Happy Time]], which did not end until convoys were introduced.<ref name="Oxford_Companion_online" />{{CN|date=September 2021}}