The party conventions are over—and I don’t just mean the 2020 conventions.
In one sense, the conventions have been over for a very long time. They were created primarily to do two things: pick presidential nominees and craft party platforms. A convention hasn’t actually picked a nominee since 1952, when Democrat Adlai Stevenson won the nomination on the third ballot.
Since then, conventions have mostly just approved nominees as foregone conclusions on the first ballot. Ever since the rise of primaries in the early 1970s, the nominee is literally chosen before the convention. All that’s left is the coronation.
But at least conventions still crafted party platforms. These are statements of principle and policy, hammered out between different factions within a party, to state clearly (or sometimes murkily) what the party stands for. Historically, platform fights could matter enormously. It was through the negotiation of the platform that a party decided where it came down on issues such as slavery and prohibition.