US President Donald Trump's decision to authorise a drone strike that killed Iran's most powerful military commander has seen tensions between the two nations escalate. What's the strategy here, and what might happen next?
Mr Trump has long promised to take American troops out of the Middle East.
But under his presidency, US relations with Iran have become more tense as he has ramped up sanctions and pulled out of a nuclear deal he viewed as flawed.
Here's what US foreign policy experts believe may be behind the decision to kill Qasem Soleimani and what it means for US-Iran relations.