Gregory: Why Trump Jr.'s Russian meeting matters

CNN political commentator David Gregory argued Tuesday that Donald Trump Jr.'s meeting with a Russian lawyer is "a huge issue" because it shows a disregard for the seriousness of the possibility of a foreign power attempting to meddle in a US election.

"Grownups in this field will tell you the Russians play a long game," said Gregory, speaking on CNN's "New Day." "They are going to attempt to infiltrate. We know from the historical record that Putin hated Hillary Clinton and wanted to interfere."

"The stunning incompetence or naivete or arrogance that they displayed to say 'oh, well, you know, we don't have to worry about anything with regard to Russia' ... for whatever the reasons, the fact that (the Trump campaign) took so unseriously the idea of Russian interference is a huge issue," he added.