The emergence of nearly 15,000 more deleted emails and evidence of shady dealings by her family’s foundation have put Hillary Clinton back on the defensive. That’s a bad place to be as the presidential campaign kicks into high gear on Labor Day.

Team Clinton is offering excuses and misdirection, hoping the press tires of the controversies and that Donald Trump creates more of his own. But the unconvincing explanations being offered create more problems than they solve, raise more questions than they answer, and bring Mrs....