Of more interest then what drove the move from closed to open primaries, is what drove the move away from caucuses and/or state conventions to government run primaries.

This is the way I’ve always looked at it. Why am I paying for something I have no chance to participate in. The parties should pay for their own primary/caucuses, not the taxpayer.

“If the primary is closed, the party can restrict its membership to white people and so keep black people from being elected.”

If there are enough people in opposition to this no-blacks policy that they could have a hope of winning the primary of the very party that has the no-blacks policy, perhaps they should form their own party, because they clearly have a large amount of clout.

If the majority of the voters are racist, the black candidate isn’t going to win the primary – or the general election, if they somehow do win the primary – anyway.

And you can always run as an independent. If the voters don’t want to vote for you because you don’t have a D by your name, that’s their choice. You have the right to tell them they’re stupid for voting that way, but you don’t have the right to force the Democrats to give you that D.

The main problem with open primaries is: Imagine Hillary Clinton runs as a Republican. All the Democrats vote for her, and the Republicans split their vote among several candidates, so she wins. Now she gets to spend Republican money on her general election campaign, get input on the party platform, and claim Republican endorsement? Shouldn’t the Republican Party itself get to decide who they actually want to run?

If that’s the rational behind open primaries, and given the fact that open primaries are the only reason Trump is the Republican front runner, I think we can say that open primaries have been an abject failure.

I agree. The parties can hold their primary elections in any way they want to, but why do the taxpayers have to foot the bill?

And IF taxpayers are going to pay, then why shouldn’t all primaries be open to all registered voters? Independents get frozen out of the process entirely in closed-primary states – and they are 43% of the electorate (as of January 2015).

I’m all for closed primaries as long as the government isn’t involved in running them.

The arguments for an open primary seem weak, on review, esp in the age of flash mobs and internet communication. My own guess is that the parties themselves see it as a prime opportunity to recruit new members regardless of the crossover risk, albeit that risk is growing.

But I’m a Canadian and so lack any firsthand familiarity with the process.

The government is merely the party in charge at the moment. So the question is what do the see as the advantage of open primaries. Depends on the election result they want as to who to allow to vote.
See ballotpedia for primary results by open/closed. (https://ballotpedia.org/Closed_primary)

Cruz seems to do better with a closed primary, while Trump excels at open. Trump fans likely differ as a group from traditional registered republicans, including crossover from otherwise democrat leaning voters. Likewise difference with Sanders/Clinton each benefiting from opposing systems.