You release he married her when she was 6 years old?
And how many times must I point out that Muhammad IS al-insan al-kamil. He is regarded as having the divine intellect. What century it was does not play out in this - because he is the man God sent - and gave him the divine intellect.
He allowed his followers to keep women as concubines after they pillaged towns and villages, but told them they must hold off sex for 3 days while the women mourned their murdered husbands.
So either he is not al insan al kamil and does not have the divine intellect, or we're all wrong. It is one or the other.
Therefore, it is against God (or that particular God who sent Muhammad) that we're working against or he wasn't sent by one.
EDIT - He did NOT marry Aisha for political reasons.
It explicitly states in the Hadith that he married her because Allah wished it.
Sahih Bukhari 9.140
Narrated 'Aisha:
Allah's Apostle said to me, "You were shown to me twice (in my dream) before I married you. I saw an angel carrying you in a silken piece of cloth, and I said to him, 'Uncover (her),' and behold, it was you. I said (to myself), 'If this is from Allah, then it must happen.