There are 4 different angles from which we can assess the situation:
1. REACTION (jUSTIFIED)
The Turkish Govt is justifed after what the Spaniards did to Cordoba Mosque. There are numerous other instances in which Mosques have been desecrated or completely destroyed.
2. POLITICAL (JUSTIFIED)
Although few visit Church in the West, yet all the Western powers will come out against Turkey (They never bothered about Babri Masjid). Moreover these very powers had no right to breakup Ottoman Empire and create 41 new states
Tourism will suffer
ISLAMIC (NOT JUSTIFIED)
Muslims are supposed to protest and not convert places of worship of other faiths
A very pertinent point has come to the fore in the article. It is about the amount paid by Muhammad the Conqueror for this place. If that is the case then Turkey has a right to use it as a mosque.