John 1 does not support the Trinity ... and certainly the author of John did not believe that Jesus was God.I disagree, primarily because that contradicts what I believe the Bible says.
John 1:1, "In the beginning was the Word, and the Word was with God, and the Word was God."
Jesus was both with God and was God. This is hard to understand unless you accept the fact that one God exists in three form: the Father, the Son, and the Holy Spirit. I, a human, also exist in three forms: body, soul, and spirit.
The first problem is the mistranslation of the term "Logos" ... which can mean "word" but in a religious context means the emmisary between Man and God.. John 1 does however argue for the pre-existence of Jesus .. which is something new.
So According to John . Jesus is The Logos .. a title like "the Adversary" but instead of being the tester of souls the job of the Logos is to bring God's word to humans .. and thus in this way Jesus is the Physical Manifestation of God's word .. "Is Gods Word" - speaks Gods word through the Holy Spirit.
So .. in the Beginnig was "The Logos" and The Logos was with God in Heaven (pre-incarnate) .. and the Logos was .. literally .. the physical manifestation of God's word. Hellenic / Platonic Philosophy .. with a little Gnostism in the mix.
None of the Early Church Fathers believed that Jesus was God .. they were subordinantists. .. believing that Jesus was subordinate to the Father. It was Tuterrlian around 200 AD who first spouted somethign resembling modern Trinity doctrine .. at the time was considered Heresy by the Church .. the squablles over the divinity of Christ raged throughout the 3rd century ... Those squabbles put to an end by Emperor Constantine who around 325 AD settled the issue declaring that Jesus was "Homoousios" .. which meant "Same Substance as the Father"
In Greek Philosophy there were two kinds of substances .. that which God was made of .. and that which everything else was made of ... so in declaring Jesus was Homoousios Constantine was declaring that Jesus was God .. and not to many gainsayed the edict of the Emperor.