At least 33 people reportedly died and more than 100 others were wounded after a terrorist blew himself up outside a crowded bank in Afghanistan. A terrorist group based in Iraq and Syria, affiliated with the Islamic State group, has claimed responsibility. (Video via Pajwok Afghan News)

During a trip to Washington D.C. in March, Afghanistan's President Ashraf Ghani warned Congress of the Islamic State group's potential influence in western and central Asia, referring to them by their Arabic acronym, "Daesh."

Ghani told Congress, "It is critical that the world understand the terrible threat that the Daesh and its allied forces pose to the states of western and central Asia."

Friday's attack bore similarities to recent attacks from last month in both Yemen and Tunisia — in both cases, the Islamic State group claimed responsibility for the massacres.

In Tunisia, gunmen attacked a museum popular with tourists. And in Yemen, suicide bombers attacked two prominent mosques. The Islamic State group claimed it was behind both, though the Tunisian government accused a local Al-Qaeda affiliate for the museum attack.

But as the Islamic State group and its affiliates try to take credit for violent atrocities around the world, the question remains, how much physical reach does the Islamic State group have past its strongholds in Iraq and Syria?

It was in June of last year that the self-declared state's leader, Abu Bakr al-Baghdadi, announced the creation of a new "caliphate" and the subsequent annexation of Algeria, Libya, Sinai, Saudi Arabia, Yemen and, later, Afghanistan.

But in reality, they don’t control nearly as much territory as their propaganda may claim. The only area they control in a manner similar to their land in Iraq and Syria is in Libya, but even there the land is contested by rival groups and Libyan militias.

But in the places where the Islamic State group is unable to obtain a physical foothold, they still wield one important tool — influence.

Loyalty pledges, also known as "bayats," from insurgent groups such as Ansar Bait al-Maqdis in Egypt's Sinai peninsula, Boko Haram in Nigeria or various factions in Yemen, Afghanistan, Algeria and Libya testify to the Islamic State group's ideological reach.

And as long as there are groups pledging allegiance to the Islamic State group, we’ll continue to see terrorist attacks bearing the Islamic State group's stamp of approval — a stamp that doesn’t necessarily mean control.