President Trump has sent a letter to Iran's supreme leader offering to reopen negotiations over the country's nuclear program. Trump warned that Iran would have to choose between curbing its program or facing a military attack. The letter's contents have not been disclosed, but it is seen as an opening bid to see if Iran is open to negotiations. Iran is currently engaged in a debate about whether to negotiate with Trump, with moderates and reformists in favor of negotiations and Ayatollah Khamenei rejecting new talks. The strategic environment has changed, with Iran's nuclear facilities now exposed to attack and its regional proxies weakened.