In 2015 and early 2016, the leaders of some of the United States’ major unions practically jumped over themselves to support Hillary Clinton for president. More significant than the fact of these endorsements was their timing: in many cases, they came before a single primary vote had been cast, and before the candidate herself had offered anything substantive in return.

It’s difficult, in retrospect, to argue that such endorsements achieved much of anything. Clinton would ultimately win the Democratic nomination and go on to run one of the most substance-free general election campaigns in modern history — pouring countless millions into personality-themed ads while neglecting to champion worker-friendly policies or hold events in labor settings. In Michigan, despite the Obama administration’s efforts to rescue the automotive sector, she did not visit a single UAW hall.

This series of events was certainly a case study in centrist incompetence, but it was also a study in the tactical ineffectiveness of many labor leaders’ deference toward Democratic elites. Rather than extracting guarantees or concessions from the Clinton campaign, early union endorsements, if anything, encouraged it to take labor support for granted.