It is troubling to watch this happen.
True enough that attendance in Christian Churches is falling rapidly, as are callings to the priesthood and ministry .
Most Muslim families consider 'wealth' according to the number of children that they have, which is 'cultural holdover' from their native lands.
Unfortunately, you can expect the number of vacant Christian churches to increase proportionate to the Muslim population.
I propose all Americans accept Allah and bow to Mecca. Read the Koran and flood the mosques! Once we are loyal followers we can become Imans and start to reform that ancient faith from the inside. Women get rights! Gays get recognized—we re-do the Koran to make it more loving and nice, maybe cut out all the violence and calls for Jihad! Once we reform Islam we can force other places to become like us! Organize a Gay pilgrimage to Mecca. We can demand all Jews become Mohammedans and bow to Mecca (or Jerusalem). We can so mess this up they will rue the day we converted. We can turn all churches into mosques— even the Vatican. No more Pope! The New Islam for all mankind!