How many times have Donald Trump's supporters and critics debated whether he will pivot to a larger, more presidential candidacy? Too many to count. So put aside any talk of pivoting — the fact is, Trump delivered a focused, powerful, and disciplined speech Tuesday night in West Bend, Wisconsin, about 45 minutes north of Milwaukee. Trump focused largely on problems that disproportionately afflict black Americans, arguing that his proposals on crime, immigration, trade, jobs, education, and other issues will improve African-American lives more than Hillary Clinton's. Trump began by declaring, "We're at a decisive moment in this election," which few...