Iraq's Kurds are caught in a three-way vice in the cross-border Iran War:They think President Trump's messaging isn't clear about regime change next door in Iran.They're under pressure to open the border from Iranian Kurds, who want to fight the regime. And Tehran's military Friday threatened the Iraqi Kurds if they allow those Iranian Kurds to plan an attack.Why it matters: The Iranian warning —the first of its kind issued to Iraq's Kurds across the border— threatens to widen the war. Iraqi Kur...