The US Senate is headed towards a vote Wednesday on President Donald Trump’s decision to embark on a war against Iran, an extraordinary test in Congress for a conflict that has rapidly spread across the Middle East with no clear US exit strategy.The legislation, known as a war powers resolution, gives lawmakers an opportunity to demand congressional approval before any further attacks are carried out. The Senate resolution and a similar bill being voted on in the House later this week face unlikely paths through the Republican-controlled Congress and would almost certainly be vetoed by Trump even if they were to pass.For all the latest headlines, follow our Google News channel online or via the app.Nonetheless, the votes marked a weighty moment for lawmakers. Their decisions on the five-day-old war — which Trump entered without congressional approval — could determine the fates of US military members, countless other lives and the future of the region.“Wars without clear objectives do