The reason is obvious: to do so would hurt Clinton's presidential chances and that cannot be permitted.
The latest batch of WikiLeaks emails show Clinton's allies in 2008 discussing then-Senator Barack Hussein Obama's weaknesses, one of which is very personal: his father's Muslim faith and his own past cocaine use.
The hacked email exchange is Campaign Chairman John Podesta's account and were sent at the start of 2008, with the subject line as a "McCain Survey." But the email discussion was actually about Obama's weaknesses after he beat Hillary in the Iowa Democratic caucuses.
One email stated: "Obama (owe-BAHM-uh) was the only candidate at a recent event not to cover his heart during the national anthem and he has stopped wearing an American flag pin."
Another: "Obama (owe-BAHM-uh)'s father was a Muslim and Obama grew up among Muslims in the world's most populous Islamic country."
And finally: "Obama (owe-BAHM-uh) described his former use of cocaine as using 'a little blow.'"
Sadly, nothing will become of these emails. The left will not discuss it, but neither will Trump effectively attack it. He appeals to his base over and over, as if they can vote more than once.
That's the problem.