I am 42, and I have been voting since I was 18. During my 24 years of voting, I have only ever been registered to vote in states and territories with closed primaries: New York (1992-1998, plus 2014-current), Pennsylvania (2000-2010), and D.C. (2010 to 2014).
When I was living in Pennsylvania, I first registered as an independent. However, in 2005 I switched to Democratic so I could start voting in primaries. In fact, the first Democratic primary I voted in was 2006, when I was actually able to vote for myself twice--both for local Democratic committee and for state Democratic committee. I won both elections. (Go me!)
In all of these places, many of my friends have been registered as Democrats, and many as independents or with third parties. Since the local primaries were all closed, I often suggested to my non-Democratic friends that they register as Democrats so they could vote in the Democratic primary (which has often been the only election that mattered, especially for local office). Sometimes they thought that was a good idea and switched, while other times they declined.
In all 24 years when I have been voting, in all the places I have voted, and whether I have been talking to Democrats or non-Democrats, until about five days ago I never once heard anyone refer to a closed primary as voter suppression. Literally never.
That isn't to say that closed primaries aren’t voter suppression. Personally, I've never thought of them that way, but times change and attitudes change. Perhaps we have entered a new era where non-partisan self-identification has become so widespread that a critical mass of people now expect to be able to vote in primaries while maintaining their status as independents. The Trump and Sanders insurgencies suggest that this might be the case, and that as such perhaps it is time that partisans such as myself bow to that demand.
However, even if that is true, abolishing closed primaries is a very new demand. Like I said, I've been voting in places with closed primaries for 24 years, and this past week is the first time I have ever heard anyone someone say that closed primaries were a form of voter suppression.
Beyond every other reason, that is why closed primaries still exist: very few people were complaining about them until the last few days. What's more, they will continue to exist unless the complaints about them continue, and outlive a single primary for a single office in a single year.
I'd like to know what you think, so I have made a poll. Should primary elections only be open to members of a political party, or should everyone get to determine party nominees? There are lots of ways to have a semi-open primary, so "mixed" is also an option in the poll. And whatever you choose, it would be great to hear your reasoning in the comments, too.