Do closed primaries ensure a 2-party system?

A closed primary guarantees that actual members of the party choose their own candidate. Why in the world should someone OTHER than a member have that privilege? As a Michigan resident, I don't get to vote in Ohio elections. As a Catholic, I don't get to vote for Worshipful Master of the local Masons. As a manager, I don't get to vote for the president of the union. Open primaries are ludicrous and should be abolished. If you want to help decide who the nominee is going to be, join the party!