CNN News:伊朗提高铀浓缩纯度 美伊关系持续紧张

Right now, though, geo-political tensions involving the Middle Eastern nation of Iran are simmering.
In December of 2019, militias supported by Iran made a number of attacks on American targets in the Middle East. The United States responded by launching air strikes against Iranian militias. The U.S. government blamed protesters trained by Iran for trying to storm an American embassy in neighboring Iraq. And on January 3rd of 2020 the U.S. launched an air strike that killed an Iranian general named Qasem Soleimani along with several other people.
The U.S. blamed General Soleimani for the deaths of hundreds of Americans and their allies and said he was planning new attacks. But Iran called the air strike an act of terrorism and promised it would get revenge.

There's another issue here as well called the Joint Comprehensive Plan of Action. It's also known as the Iran Nuclear Deal. It was a controversial agreement reached in 2015 between Iran and six other countries led by America's Obama Administration. In the deal, Iran agreed to limit its nuclear program which the other nations opposed.
And they agreed to remove their sanctions on the Middle Eastern nation which were worth billions to Iran's economy. But in 2018, America's Trump Administration pulled the U.S. out of the Iranian Nuclear Agreement calling it a bad deal. And Iran recently went back to enriching uranium at a higher purity which could help the country build an illegal nuclear weapon, though Iran says its nuclear program is peaceful.