I think it is quite OK for them to do what they want so long as the events are remembered by museums and memorials. It is presently recent history only for old farts but fast fading into old history for the world as a whole.
Almost every inch of Europe and Asia have been swept over by battles far larger and more costly than anything that happened on D-Day (the whole campaign not even in the top 10 for WW2) and they are simply recorded by various markers and a page in a history book - many not even that.
Even the "recent" history of the millions lost in WW1 battles has faded from the collective memory and is commemorated mainly by graveyards and a relatively few museums and town memorials. Much of it is now covered by freeways and towns.
Life goes on, the world keeps turning and once those directly connected to events fade away they become mere footnotes in school history books overtaken by more events relevant to today.
These in turn (no matter how big or far reaching) will eventually be consigned to the pages of irrelevant history as current problems naturally arise. This is the condition of man.
If
we are interested
we should be doing something about it. How far back do governments have to go?
Lang
For those who are interested this consolidation from Wiki puts some perspective on it.
https://en.wikipedia.org/wiki/List_o..._by_casualties