Wow! Is that right?
I prefer not to learn Islamic history from an atheist, mind you. I wonder who started this war?
My opinion is that the Quraish wanted to kill Muhammad and his followers and had to leave Macca because of it. The quraish felt threatened .. not from violence .. no .. but that they might lose some power & wealth.
Isn't it always the same. Atheists or hypocrites with some kind of agenda, that wish to kill Almighty God's chosen prophets. ie. 'put the light out' Well .. on this occasion, they were not successful.
There were no war between Medina and Mecca, until Muhammad began leading raids upon the Meccan trade caravans, from 623 to 624.
Why shouldn't the Meccans defend their goods from Muslims who acted nothing more than robbers or pirates. This is not the act of self defence, but Muslims trying to gain wealth, not through honest employment, but from harassing trades just as pirates would do.
Muhammad began the war, not the Meccans.
And Muhammad's persecution in Mecca before his exile, was the direct result of Muhammad threatening the pagan Meccans with the destruction of idols, with his sermon or preaching. Muhammad was the one who was inciting those who would follow him to destroy religion of people who disagree with his religion.
Muhammad's persecution and exile to Medina was his own doings. If Muhammad make hostile speech, do you seriously think that the Meccans wouldn't feel threatened?
Like A Greased Scotsman wrote, Muslims were the ones who took hostile and aggressive action against Ta'if before his death. And the Ta'if were given much of choice when the Muslims came at them the 2nd time, and the condition of accepting surrender were that the people of Ta'if had to convert. This make the whole no compulsion in Islam, a meaningless farce.
After his death, they (Muslims) were the ones who attacked the Byzantines and the Persians, and these were not the acts of self defence. The whole "we will only fight in defence" is nothing more than a ploy and propaganda.
And the history is that are mainly from Muslim sources. There are no atheist sources.