The firing of James Comey has restarted a conversation about the vulnerability of public institutions in America that had gone largely dormant.

Before Tuesday, one of the most remarkable things about Donald Trump’s presidency was how sturdy it had shown competitor institutions, and the larger system of checks and balances, to be. Courts have beat back his power grabs; media, for all its flaws, has been more skeptical of the claims and actions of the Trump administration than of any administration in recent history. Civil society organizations have flourished, and a vital protest movement has both slowed the GOP legislative agenda, and forced some Republicans in Congress to expect a measure of accountability from the White House.

For those who were relieved by this, Comey’s firing should be a frightful awakening from complacency.

The immediate threat of the Trump presidency wasn’t that he would sap the public of its civic-mindedness, or intimidate judges and reporters into submission with his tweets. It was to the institutions under his control—the ones within the executive branch—and particularly those with meaningful independence from political actors in the White House. Because the path to neutralizing or coopting external institutions runs through corrupting internal ones.

In his first weeks as president, Trump appeared to lack both the aptitude and the dedication required to do this. Yes, he corrupted the government, but it was through laziness and greed, so the effect was limited. Trump was satisfied with a bargain whereby Republicans in Congress set most policy, and in return they turned a blind eye to his self-enrichment.