Paul, thanks for clarifying my point, but I am going to take issue with your analogy.
Every country does have its plethory of patriotic songs, but if such songs had influenced Britain in 1914, we would have joined Germany to fight the French!
Remeber too that Irishmen enlisted with as much enthusiasm as Englishmen.

I am saying that the rebel songs have helped to create a false history of an oppressed Irish people united in hatred of an English oppressor, and that these encouraged impressionable young men to believe that they were joining a centuries old crusade that never really existed.

I am also suggesting that these songs began appear in the latter half of 19thC, predominantly in USA, where they were produced by professionals writing for misty eyed descendants of immigrants, and did not become popular in Ireland before the rising.

(How am I doing Martin?)