Why Do Most European Countries Ban Mail-In Voting?

Several weeks ago, my wife and I received postcards from Massachusetts Secretary of State William Francis Galvin instructing us how to apply to vote-by-mail in the upcoming elections in the Commonwealth. The question is:  Why?

Several weeks ago, my wife and I received postcards from Massachusetts Secretary of State William Francis Galvin instructing us how to apply to vote-by-mail in the upcoming elections in the Commonwealth. The question is:  Why?…