As the United States has unveiled their rigid sanctions with Iran in regards to their denuclearization, the world’s eyes are once again turned to the country to see how it will respond to financial threats. Sanctions coming from a country like the U.S. have historically been seen an alternative to real action to appease public opinion, but sanctions like this can have real, devastating effects — especially when coming from a consumer-heavy nation like America.

Many people think in different terms when it comes to the Middle East and its surrounding countries — some think in clusters. You’ve got the cluster of Saudi Arabia, Iraq and Iran all encroaching on Syria, Jordan and Israel. Eventually you have Turkey to the north. Then to the east, you have the Afghanistan and Pakistan cluster, and some might throw Turkmenistan and Uzbekistan in there too. Other people think in different groups — some may put Iran in a separate category altogether. Generations who are familiar with older conflicts might cluster other countries together in different combinations.

Whichever way it’s cut, the border of Iran and Afghanistan makes the news every so often, but the two are often not thought of as the direct neighbors that they are. They share almost 590 miles of border (945 km), and have a lot of controversial traffic that moves between them.

The U.S. presence in Afghanistan is right in Iran’s backdoor — this gives the U.S. a great strategic advantage in any aggression that may play out with Iran, much like the U.S. presence in South Korea as it relates to North Korea. This is the first obvious concern from the Iranian government as far as their poor U.S. relations go, but it goes deeper than that. The Afghan government is quite obviously in league with United States interests, and they are liable to enforce those interests even after the U.S. hypothetically pulls out. The Afghan government struggles with a lot of corruption, and whether or not they will withstand a U.S. withdrawal is up in the air, but the Iranian government is undoubtedly going to have concerns regarding a neighbor whose government was literally installed by their harshest international critic.