Do you think this Christ fellow everyone seems to adore so much thought that you should march off in battle and slay the heathenish? I'd tend to think he was more inclined toward sitting down over a bottle of wine and breaking bread and discussing things other than the most advantageous way of staving off mutual annihilation.
How about we have just one Church. We can make it a big round 500 story building in each City. Inside the front door you will find doors leading to the elevators that will take you to your proper place of worship. The Amish will be allowed space on the first dew floors to avoid being forced to utilize new fangled inventions. The Islamic sects will be allowed to have an open minaret at the top to chat prayers from, or a smaller one down around ground level off toward Mecca.
The extreme sects will be afforded space high enough that their mass suicides will be assured success and over a catch basin to make cleanup easier. All true faithful Jews, Christians and Islamic recognize that there is only one God, they even agree that he was the God of Abraham, so they should have no problem accepting that theirs is the true temple of God, and it is a huge Mansion with many rooms.
The Hindu may need to have the back side of the building to allow the free entry of cattle, monkeys and other reincarnated or acesended souls. And they should be kept away from the ritual animal sacrifice religions, I'm fairly certain that the Amish would be right at home with the Hindu but some of them might take to worshiping the Amish livestock.
We can even build a stadium into the structure and let the Christians and whoever they are pissed at this week battle it out and keep the carnage contained. And just imagine the ticket sales to a great 10 hour all out death match between two factions be it the FBI and Extreme Right Wing Fundamentalists or a slower, more refined Catholic and Protestant hit and run action.
The Knights of Malta Hospitaliers and Sisters of Mercy can be kept busy patching up the survivors. In addition to sports/combat stadiums the Temple can accommodate shopping, banking, civil departments, restaurants and apartments so that those that wish might never need to leave the building and be exposed to the Heathen World outside the Holy Temple Grounds.
Then we can stop being concerned with World Wars being fought over Religion, Political Leaders creating public policy based on the belief that they are divinely manifested to guide the World to his one true faith.