My sister is taking AP history right now and she came home not to long ago and mentioned that via the columbian exchange Britain of the time essentially committed biological warfare against a people. And that this was wholly to blame for the general depopulation of that culture.

Do they teach this everywhere and what are your thoughts?

Personally I want to ask, in what way could anyone of the time have forseen that their species carry all these diseases with them, across the ocean. And even if they had, did they want them to wear hazmat suits in the 1400's?

Anyway would love to hear opinions, as this seems like a false teaching to me.