I'll cover that eventually, but you must understand that there are times when God Himself may call a man to grow his hair. Check Numbers 6.... that was God's idea, not man's.
Personally, nature is not my teacher, and I'm not here to glorify myself. I think that Paul here was describing the world, and that society will often reject men with longer hair. That would also coincide with what God was doing when He created the nazarite vow in Numbers 6. He was calling a special people unto himself to be set apart from this world.
Please note, 1 Corinthians does not state, "It is an abomination unto the Lord for a man to have long hair." For some reason, people seem to read it that way. I hope this helps.
Edit: I do not believe that a Nazarite vow can be taken now nor am I claiming to be a nazarite. I am just providing that as an example to show that people use what Paul said there to mean something different than what it actually says.