[Aktungbby]

Originally Posted by Jimbuna

1941 Prior to US joining WWII, German submarine U-552 torpedoes US destroyer Reuben James near Iceland.

actually had bad results for the Kreigsmarine:

On 31 October 1941, USS Reuben James was one of five destroyers escorting convoy HX-156, close to the coast of Iceland, about 600 nmi (1,100 km; 690 mi) west of the island. Reuben James had just begun turning to investigate a strong direction-finder bearing when a torpedo launched from U-552 struck her port side and caused an explosion in her forward magazine.[12] The entire bow section of the destroyer was blown off as far back as the fourth funnel and sank immediately. The stern remained afloat for around five minutes before sinking; unsecured depth charges compounded the damage, exploding as they sank and killing survivors in the water. One hundred and fifteen of her 160-man crew were killed, including all the officers.
The destroyer was the first US Navy warship to be sunk in World War II.
The incident provoked a furious outburst in the United States, especially when Germany refused to apologize, instead countering that the destroyer was operating in what Germany considered to be a war zone and had suffered the consequences. The sinking of the Reuben James did not lead the US to declare war on Germany; it did, however, provide a pretext to officially transfer the US Coast Guard from its peacetime role as an arm of the US Treasury Department to a wartime function as part of the US Navy. Congress also amended the Neutrality Act to permit the arming of US-registered merchant ships and authorized them to enter European waters for the first time since 1939.