Hillary Clinton Picks VP,Obama.

The 2016 presidential race will be defined by the relationship between two titans of American politics: Barack Obama and Hillary Clinton. For the first time in more than two decades—since President Reagan campaigned with then-Vice President George H.W. Bush—an incumbent two-term president will be an active player in the campaign and possibly even an active presence at events.

Right now, President Obama is free to be the designated partisan attack dog for Mrs. Clinton, allowing her to remain above the nastiness likely to arise in a race with a sharply divided electorate. Bill Clinton has played that role for her in past races. This time Mr. Obama’s presence allows Mr. Clinton, with his high poll numbers, to lead a chorus of nostalgia-stirring reminders of good feelings about the last time a Clinton was in the White House.

[link to www.wsj.com]