Re: Islamically can you join a national army...
USResident, that is what I meant when I said "I know where you're going with this..."
These are ayat from the Quran:
Unless you had 3 or 5 prayers there would be no middle prayer to guard. This is talking about prayer at Asr time.
Two ends of the day means beginning and ending of the Day i.e. Fajr and Maghrib prayers. Dawn to Dusk.
Again references to maghrib, Isha and Fajr.
Again references to Fajr and Isha.
It doesn't get any clearer than this that routine prayers were prescribed for the muslims, details of which are given in ahadith. If you wish I can present numerous other verses about the actions performed in prayer i.e. bowing, standing and prostration.
As I said I did not leverage the ahadith to show that prayers existed before the compilation of ahadith and the advent of ahadith did not introduce ritualistic prayer as you have stated.
The only thing I expect now is you will propose some new form of translation of these verses and change the meaning. If you want to we can still go ahead and go through that as well.