Arabs and their neighbors have been known as fearless and proficient warriors from their time began as it is in their DNA.<quoted text>
Again you are missing the point, if our prophet was attacking and killing "every one" who did not believe in him, the number of persons killed would be much higher.
That shows , he used the force very carefully and that too within the limits that was absolutely necessary, that is why he got so much spectacular results, which are unmatched in whole religious and / or secular history of any nations.
For your info, Arabs were no cowards and not were not used to fighting and killing. Their internal strives continued for many decades and resulted in much blood shed!!
So just do not just imagine things, talk of hard facts.
Nothing is hidden in the life history of our prophet.
Read your own words of the history you have informed us of how Muhammad overcame his opposition in his quest for control over them.