While History indeed accounts to such truth - the pages of our books still echo of the many battles, invasions, and persecutions nations have faced before Arab hegemons, Terror, that we experience today, is also rooted in colonialism; the expression of a socio-political malaise fallen empires failed to address, so quick were they to dismiss their responsibility vis a vis those communities which now populate their national landscape.
If Terror's militants have chosen to exert their wrath on Europe's streets it is because Europe sits as a designated enemy, the old enslaver and conqueror, who now, dictates and shapes geopolitical realities from afar. If Europe no longer sees itself as a colonial force, the former colonies have yet to outgrow such stigma.
Comment: It's surely preferable to being laid off and, whilst the military is needed for a reason, it does show how the efficiency of the personnel can be utilised in other ways: