WASHINGTON—The U.S. Senate on June 23 passed a resolution seeking to prevent U.S. forces from engaging in further hostilities with Iran unless they are first authorized by Congress. Senators voted 50–48 in favor of a concurrent resolution to constrain President Donald Trump’s ability to make war against Iran. The resolution was previously passed in a vote in the House of Representatives on June 3. The war powers resolution, which was presented pursuant to the framework set out in the 1973 War Powers Resolution, offers a symbolic rebuke of the military campaign Trump launched against Iran on Feb. 28, but lacks clear legal enforceability without the president’s signature....