help developing idea into a plot

Philip K Dick did an alternate history of WW2 called 'The Man in the High Castle' I haven't read it so can't comment other than it's been recommended to me a few times so its on the list. I actually just read 'The Undertaking' by Audrey Magee (an Irish writer) which presents the battle of Stalingrad and sacking of Berlin from the German POV - not one of my favourite books ever but Magee manages the objectivity well - the scenes of shell-shocked soldiers and those at the front struggling to survive are unusual and quite moving.

I remember as a teenager reading a book called 'Summer of my German Soldier' - aimed at the young adult market but also putting a more human face on the political madness. One of the most heartbreaking anti-war novels you'll ever read is 'All Quiet on the Western Front' - from the German POV but set in WW1.

Of course if your plan is to try and argue that the Nazi regime was merely misunderstood with it's book-burning ways and anti semitic, anti black, gypsy, gay, female, religious, disabled and so on and so forth philosophy I'd say you've taken on an impossible challenge.