I think you are missing my point, you said the British and the Scottish had been at odds since the 1300's, which isn't true. What I think you meant is that the English
and Scottish have had some differences since the 1300's.
You said America sided with the English during WWII, which is true to a certain extend. But it wasn't England specifcially, but the United Kingdom of which England is a part that Ameriuca sided with as part of the Allied Powers.
Don't refer to England when you actually mean the United Kingdom.