You seem to sugest that Christianity as an ‘interloper’ has somehow no real moral or historical authority to be there. By that standard, no religeon has any right to be anywhere, since you can always find some other beliefs that predated it. The fact is that the establishment of Christianity in India was not based on conquest, as was the case with Islam.
But if a group of people have been practicing a particular belief system for millenia, its natural for some of them to resent a new belief system appearing in their midst.
This would not be an issue in most Islamic Nations as they simply do not allow religions other than Islam to be practiced there or the missionaries are simply killed or deported.
This situation has to be viewed in historical context.
If you want to get angry at something, get angry at the fact that our government has expended lives and money to install a regime in Baghdad which is far less tolerant of Christians than the military dictatorship we removed. Be angry at the fact that our government, regardless of which party is in office, panders to a lunatic state which allows NO other religion but Islam to be practiced there, and then only the most virulent form of that religion - Wahhabism (Saudi Arabia). Be angry at the fact that when people were being massacred in the Sudan on the basis of the fact they were Christians, it was not an issue, but when it became a matter of religion, it was considered a world tragedy.
ISLAM is the enemy threatening Christianity, NOT Hinduism. Hinduism never was and Islam has been since the moment of its conception.