Lawmakers see Iran's rise as key concern in fight against IS
Republicans focus on Tehran in first hearing since Tikrit offensive.
Iran has emerged as a main issue for Congress as it debates whether to give President Barack Obama the powers he wants to battle the Islamic State (IS) in Iraq.
In their first hearing on the issue since last week's assault on Tikrit by Tehran-trained Shiite militias, members of the Senate Foreign Relations Committee on March 11 repeatedly asked US officials whether defeating IS would only empower Iran. Most senators had no ready solutions to offer, but several suggested a beefed-up US presence was the only way to keep Iran in check.
