The term radical is largely capacious as it may transform meaning which you want to put into it. Historically it was used in 18th century to extend franchise by English people. Google tells us that today many crops parliamentarian cannot go without it since it has been becoming a word used for politics. If you put word Islam before it then it becomes bogey word.
Radicalization hypothesis suggests a state of frustration with international or national events in which crops of people or group rejects any kind of societal change which they perceive as perilous. Key drivers of radicalization namely extremist theology, common grievance and little know how about jihad are of major concern for riots in a country. This hypothesis points us wrong direction when Muslims are recognized as radicals. Muslim theology originates from Quran, a holy religious book for Muslims as guidance for code of life. But young lad who joins extremist movements is victim of religious rhetoric and hardly covered just one aspect of bits of murder and nothing next to know about Quran . Quran prohibits murdering guileless civilians of any sect. Another source of Muslim theology is Hadith, sayings of Holy Prophet (PBUH) in which Holy Prophet stringently condemns slaughtering innocent children, females and old people in combatants’ tribe even when opposing in a battle with antagonists.
Young Muslim lad is motivated to join extremist movements when they perceive their country is under attack by foreigners. It’s just retaliation to western misguided intervention in South Asian region. The people who go off to fight in Afghanistan are not motivated by religious rhetoric of false leading extremism but they believe that NATO forces are invading their Muslim tribe and murdering Muslim brothers.
It is historical fact that western misguided adventure of transforming world into its colonial system has root cause of rebel actions against government. A joint struggle of Hindus and Muslim in 1857 to fight for sake of freedom from foreigner’s invasion in Hindustan poses a surge of extremism and riots in country against English Army which reflects indignation against change in societal norms. Then English Army quelled common grievance among locals by force and then history observed bloodshed in state. It unfolds British brutal political endeavor of Hindustan’s subjection to European colonialism. So, the word radical has its root deeply in politics rather in conservative Islamic terrorism.
The long history of disastrous western intervention in the South Asian Region is part of cause of horror so west has to face its responsibility for terrorism. Eradicating extremism involves cease to interfering other tribes and countries, let live the people according to their norms and values. This would bring peace and hinder young Muslim lads from joining any extremism movement.
In fact if you want to find a terrorist, look for people who buy dodgy chemicals, not for people who are offering their prayers.