Despite a couple of appearances on behalf of Democratic candidates, Barack Obama has adamantly refused to heed the pleas of his party to lead the “resistance” against Donald Trump and instead spends much of his time at his home just blocks from the White House playing video games, chatting on the phone with celebrity pals, smoking marijuana and popping cannabis-infused gummy bears. This startling description of Obama’s post-presidential life is based on interviews with a close Obama family friend who has been a sleepover guest at the Obama home in the Kalorama section of Washington, D.C., and who has...