President Donald Trump’s pledge to dismantle the Dodd-Frank financial overhaul is colliding with the same reality as his pledge to gut Obamacare: The Republican majority in Congress can’t decide how to make it happen and Democrats are vowing to fight. Trump, who last month said Obamacare would be replaced “the same day or the same week,” or perhaps “the same hour,” acknowledged Sunday that the health-care law isn’t going away anytime soon.