Jack Northrop wanted to start development on a flying wing in 1923 but was unable to do so due to the economy and lack of funds.
His and the Horten brothers (sorry for the misspelling earlier) progress and developments were so closely paralleled it is near impossible to say truthfully "he designed it first, they copied him" or vice versa.
My point was simply that the Allies had innovative designs also, not just the LW. Many of them were never fully developed because there was no need, the Allies were winning the war with what they had. Too many people see a picture and automatically say "oh, that has to be a German/Luftwaffe design. Look how advanced it is."