T The two most important roles for journalists during political primary season are to cull the herd of the weakest candidates and take their best shots at the frontrunner, to test his or her readiness for the general election. That's a public service for the political ecosystem.

So a profoundly weak frontrunner should be the ultimate in big game for our top political reporters.

Instead, mainstream journalists in the best positions to demand answers — during sit-down interviews and televised debates — have been remarkably gentle with Joe Biden.

They ask about his decision to authorize the war in Iraq, but not about the many documented times he has lied about why he made that decision, and when he first realized the war was a mistake.

They ask questions about his fitness for office, but let him off with glib answers about push-ups rather than assertively confronting him with examples of his consistent and troubling incoherence — even when he is in the process of giving them fresh examples.

We’re entering a critical period in American politics and American political journalism is not up to the task. Donald Trump’s campaign and presidency have exposed and exploited chronic weaknesses like never before. And despite some progress, elite political press coverage insufficiently rebuts lies; normalizes abnormal behavior; asserts false equivalences; remains overly susceptible to spectacle, conflict, and gamesmanship; fails to contextualize the news with expertise – and on and on.