In the spring of 2019, U.S.-Iran tensions have escalated. The Trump Administration, following its 2018 withdrawal from the 2015 multilateral nuclear agreement with Iran (Joint Comprehensive Plan of Action, JCPOA), has taken several steps in its campaign of applying "maximum pressure" on Iran. Iran or Iran-linked forces have targeted commercial ships and infrastructure in U.S. partner countries. U.S. officials have stated that Iran-linked threats to U.S. forces and interests, and attacks on several commercial ships in May and June 2019, have prompted the Administration to send additional military assets to the region to deter future Iranian actions. President Donald Trump, while warning Iran not to take action against the United States, has said he prefers a diplomatic solution over moving toward military confrontation. The Administration has expanded U.S. sanctions against Iran, including sanctioning its mineral and petrochemical exports during May-June 2019, placing further pressure on Iran's economy. Iranian leaders have refused to talk directly with the Administration, and they have announced an intent to no longer comply with some aspects of the JCPOA. U.S. allies and other countries such as Russia and China have expressed a preference to reduce tensions. Several countries, including Japan, Germany, Oman, Qatar, and Iraq, have sought to de-escalate U.S.-Iran tensions by sending high-level officials to Tehran for talks. An expanding action-reaction dynamic between the United States and Iran has the potential to escalate into significant conflict. The United States military has the capability to undertake a large range of options against Iran in the event of conflict, both against Iran directly and against its regional allies and proxies. However, Iran's alliances with and armed support for armed factions throughout the region, and its network of agents in Europe, Latin America, and elsewhere, give Iran the potential to expand any confrontation into areas where U.S. response options might be limited.