If thousands of American Indians died at the hands of the Europeans and an estimated20-70 MILLION died due to disease, would it still be fair to say that the Europeans are responsible for their genocide?

It is the Europeans who brought over the disease that led to this genocide, yes. But it seems though that even if the Europeans came in peace the diseases that they carried would still have been deadly enough to wipe out the majority of the American Indian population.

So technically speaking, the discovery of The New World by the Europeans would have led to the disease based genocide of the American Indians regardless of whether they came in peace or not... Right? Or maybe not?

If someone could shed some light on this subject it would be greatly appreciated (Also, I apologize if the term "American Indian" is politically incorrect).