I say No, that would have to be one very powerful dictator with a lot of very strong allies to be able to take down the whole world. Because there will never be a time when everyone has the same beliefs in politics, religion, etc.
It would be. My denomination has been called several things. We have been call protestant, baptist, independent fundamental etc. you pick what you want to call me there all the same thing
I call myself independent fundamental. But if you except Christ as your savior it really doesn't matter what denomination you are because you are going to heaven with all the other saved people on earth.
We are called independent because in the late 1800s to early 1900s we strayed away from the religions of the time (i.e. methodist and catholic) and created our own independent religion and have not entered any of the common conventions or associations. Most IFB churches use the KJV version of the Bible and believe that the only way to heaven is by trusting Jesus as your personal Savior.
One world leader would lead to disaster. All the nations would try to buy him or her off to get some power over the others. Sithman is right on about the anti-christ. He'll fool everyone into believing he's what the world needs. He'll be nothing but a phony.