Feta first started addicting and overdosing Soviet soldiers in Afghanistan in the 1980s earning him a reputation as a 'friend' to the West. Later, as Radical Islam declared the West to be the Great Satan, Gulen stated accurately that it was impossible at the time for Islamic countries to defeat the West militarily but could be weakened through drug addiction "bring them down with the needle" just as Soviet soldiers had been in Afghanistan. His illicit narcotics have caused unprecedented addition in America from Kentucky to California as communities fell into economic decay while American industries relocated to and sourced from China and the Asia region.
Gulen later tried to overthrow Erdogan in Turkey (some say as an agent of Hillary Clinton as part of the 'Arab Spring') but failed (General Flynn was involved with getting evidence on Gulen which is one reason he was targeted by Democrats). Gulen escaped from Turkey and was given safe harbor by friends of Clinton. It is a reasonable speculation to connect Gulen's safe harbor with his billion dollar subaccount for Hillary Clinton.
During Obama's presidency, Gulen posed as an 'Imam' and set up more than 150 Islamic 'schools' in the US using grants from the US Government.
Gulen's network in the US is reported by many to have used his Islamic 'students' and placed them in employment under the Democrat controlled SEIU. The report is these SEIU employees would work in VA hospitals as pharmacy techs or janitors where they would change out opium based drugs in locked cabinets with products originating from Feta's poppy farms in Afghanistan resulting in deaths of US Vets. These SEIU employees would thus commit 'revenge killings' against the US military role in Afghanistan.
Very bad guy, worse than Suleimani because he's connected 'inside' the US Democrat establishment.