WASHINGTON—In a dramatic reversal of recent polls showing a decline in the president’s approval ratings during his first 100 days in office, new surveys confirmed Tuesday that President Donald Trump’s support was surging after he pointed a gun at all 340 million Americans. “Ever since Trump pulled out a loaded handgun and menacingly swept its muzzle across the entire American populace, he’s seen a massive bump in favorability on everything from his handling of the economy to his views on immigration,” said Gallup polling analyst Eric Waltman, adding that Trump’s numbers had seen a particularly sharp spike after he fired a shot into the air to show that “he means business.”