Long Division

This has really began to irritate me. This may be offensive so if you are are feeling particularly sensitive just go to a different site. I want to ask why there are so many denominations that fall under the Christian umbrella (excluding those that deny fundamental teachings from the Bible)? Have you really sat down and thought about it? We as the body of Christ should be acting unified, but we aren't like that when we look at the fact that there are so many denominations. I have nothing against baptists, Presbyterians, Methodists, etc... but I do have an issue with the fact that we are not acting like a unified movement going into the entire world.