Maybe I missed a reference somewhere. Maybe Clinton plans to discuss Obamacare sometime in the future. But the point remains: When Hillary Clinton takes to the stump to campaign, her party’s signature achievement is nowhere to be found.

At Clinton’s highest-profile appearance in September — her debate with Donald Trump — moderator Lester Holt did not bring up Obamacare. Clinton could have mentioned it herself but did not.

Remarkably, Trump didn’t bring it up either. That is surely frustrating to Republicans who hoped to make the Democrats’ struggling and burdensome health care scheme a major issue in the debate, and the campaign as a whole.

But put aside Holt’s and Trump’s omissions for a more fundamental question. If Obamacare is so great, why isn’t Hillary Clinton talking about it?