Is History One Big Circle of Plagiarism?

I have always been fascinated by history, and sometimes it's incredible that the more you learn it, the more you realize that that don't know enough about it.

Until 1942, in the US, the Pledge of Allegiance to the flag was different than it is today. Instead of the custom of someone placing their hand over the center of the chest, the pledge involved a salute where someone would hold their hand outstretched, and slightly upward.It was known as a Bellamy Salute, this is an actual picture of the pre-1942 ritual. a class of elementary students saluting the flag.

Now why does this picture look rather disturbing? Doesn't it seem eerily familiar?

This is why it seems too familiar:

(Bottom picture: Spectators at the 1936 Berlin Olympic games)

Now you know why the US changed the salute for the Pledge of Allegiance in 1942?

Both gestures are also very similar to the Roman salute, which as it's name implies, claims to have it's origins in the ancient Roman empire. If true, then one of the world's worst nations for historical plagiarism was plagiarized, because ancient Rome copied most of their deities from ancient Greece, and simply renamed them, and gave them slightly different life stories. 

Another example of a fascist empire duplicating Rome is a symbol used often by Mussolini's fascist empire in Italy. This was the symbol of Mussolini's infamous "black shirts", the thugs used to intimidate political opponents and civilians alike, it's name is the fascio, and it too, comes from ancient Rome, and is in fact the origin of the term "fascist".

So, it begs the question, is history just one big circle of plagiarism?