By double-digit margins, swing-state voters prefer the former president over Harris when it comes to dealing with both conflicts. WASHINGTON—With wars in Ukraine and the Middle East looming over the U.S. election, voters give former President Donald Trump the edge over Vice President Kamala Harris on who would better navigate the country through both conflicts, according to a new Wall Street Journal poll of seven battleground states. Trump leads Harris among swing-state voters, 50% to 39%, on who is best able to handle Russia’s war in Ukraine and has a wider advantage, 48% to 33%, on who is better suited...