In the first claimed attack by ISIS in Iran, a group of six heavily-armed assailants mounted simultaneous assaults on the Islamic Republic's parliament building and the tomb of revolutionary founder, Ayatollah Khomeini. Using assault rifles, grenades, and suicide bombs, they killed at least 12 people and wounded dozens before security forces finally took control of the situation and killed all six attackers.

The audacious assault in Tehran comes during what the New York Times described as a "nonstop staccato of terrorist attacks in the last few weeks around the world." These include this weekend's van attack in London, the Manchester bombing on May 22, the shooting of a French police officer on April 20, a truck attack in Stockholm on April 7, a suicide bombing in St. Petersburg on April 3, and a previous attack near London Bridge on March 22.

But while those attacks brought out heartfelt tributes, anguish on social media, and a cascade of news stories, most people barely even registered the attack in Iran. Was it the because the incident took place in a predominately Muslim country? Or because there was already too much happening on a fast-paced news day?

Or was it, as this map suggests, selective grieving? Have we been conditioned to think that life is just "like that" in the Middle East?

The attack in Iran carries a great deal of context behind it, which is hard to explain over social media. This could be another reason it hasn't seen the same reaction as the attacks in the United Kingdom and Europe.

ISIS' attack on Tehran is the first by the Sunni terrorist group, which views the Republic's largely Shiite population as heretical. Iran is also supporting Iraqi (and U.S.) efforts to fight ISIS in the region. Iran is seen by other Persian Gulf nations as a pariah state, and has been heavily criticized by President Donald Trump's administration for its actions in the region.

The White House even suggested that Iran's support for militant groups was responsible for the blow-back it experienced on Wednesday. (Saudi Arabia alleges that Iran is providing material support to Houthi rebels in Yemen, a country Saudi Arabia is currently bombing with the assistance of the United States and other Gulf nations.)

Iran, in turn, has blamed Saudi Arabia for the attacks, referencing President Trump's visit to that country in a statement that declares "this terrorist attack happened only a week after the meeting between the US president and the backward [Saudi] leaders who support terrorists."

Iran does have one ally in the region: the tiny, wealthy country of Qatar.

That country has also been at the center of a storm of controversy, as other Persian Gulf nations have accused it of sponsoring terrorism. Saudi Arabia, which shares Qatar's only land border, and several other countries have cut off diplomatic contact and trade, and issued its government a list of demands to expel members of various terror groups.

Complicating matters even further is that Qatar is also the home of a major U.S. airbase, which is a launching point in the war against ISIS. While Secretary of Defense James Mattis told reporters that the situation with Qatar had "no implications" for the ISIS campaign, that statement was made before the attack in Iran.

Iran and Qatar now find themselves pitted against a coalition of Gulf countries aligned with the United States, despite the U.S. having major military assets in Qatar and working with Iran in the fight against the terrorists who attacked Iran.

As the situation in the Middle East continues to become more difficult to follow, Americans appear to have already moved on from the attack.

That leaves 12 people dead in an attack that's merited almost no reaction among people already fatigued by grieving over distant violence.