WASHINGTON (AP) — While in office, former President George H. W. Bush once plaintively asked, “What is it about August?”

Indeed, this sultry month usually associated with the doldrums of summer has burdened modern presidents with personal, domestic or international crises. And for President Barack Obama, who returned to Washington Sunday from a two-week Martha’s Vineyard vacation, what remains of the August calendar looks perhaps more daunting than when he left.