Ed Husain is a commentator and writer specializing in Islam, the West, and the modern Middle East. The opinions in this article belong to the author.

(CNN) World leaders gathered this week in Riyadh, Saudi Arabia , to seek peace and condemn religious radicalism. At the very same time, a suicide bomber was preparing to kill innocent, fun-loving people at a concert in Manchester, England.

Unless we identify and change the persuasions of the people who want to kill us for being free peoples, we will not be able to stop the scourge of global terrorism.

We are not witnessing accidents and coincidences. The mass murderer, who killed 22 innocent people, chose his target for a reason: He hated their freedom to laugh, love, dance and enjoy music.

Most in the West find this level of intense religious conviction hard to grasp, but that is the frame of mind that we are up against.

I am an observant Muslim, and I have been watching the rise of this Salafism in our communities that leads to jihadism across the world.

Their jihad is not ultimately against concerts and clubs. Their jihad is for the support of a caliphate that will confront the West and Israel. ISIS is the outcome of that decades-long craving among Salafists and Islamist activists for a caliphate, or an Islamic state.

In this pursuit, they compete with Iran. If Iranian Shia Muslims can have a government based on their Shia interpretation of Sharia as state law, imposing burkas on women and punishing adulterers, then where is the Sunni Islamic state?

To that end, a host of Salafi and Islamist groups fight to impose their reading of religion on societies by taking over governments. Worse, they believe that unless they revolt to take control of countries and constitutions in the name of God, they are deeply sinful and will burn in hell.

They bully and cajole ordinary Muslims around the world with this narrative: Support us in our claims for a caliphate, oppose Muslim governments and the West, and if you don't, then you are sinful; if you speak against us, you are an apostate, and we will kill you.

JUST WATCHED Details emerging in Manchester attack Replay More Videos ... MUST WATCH Details emerging in Manchester attack 01:58

This is the deeply political, ideological and theological war in which we are all engaged. The good news is that the vast majority of the world's Muslims are not Salafi jihadis. The vast majority of the victims of ISIS, Boko Haram, Hezbollah and al Qaeda are Muslims. Terrorist attacks are stopped when normal Muslims tip off the authorities. In Manchester, it was Muslim doctors and taxi drivers that rushed to the aid of the victims.

In 1979, when the revolutionary Iranian government created its theocracy, Islamist terrorism was a problem in Egypt and Iran. Today, more than 40 countries around the world are fighting Islamist radicalism and terror. When 9/11 happened, al Qaeda was a ragtag army of several hundred. Today, jihadists in Iraq and Syria are estimated to be more than 30,000 strong . Then we have Hamas, Hezbollah and a cluster of others.

But we can and will win.

When President Trump called on Muslims from Riyadh last week "to drive out the extremists," he did not mention how. Speaking immediately after him was King Abdullah II of Jordan. Eloquent and direct, he was right in saying that groups such as ISIS were not only on the fringes of Islam but are Khawarij and are outside of Islam.

He was reminding Muslims globally that when a cult inside early Islam started to kill en masse in the name of God, Muslims banished them from within Islam. The fourth caliph, Imam Ali, fought them and killed them.

King Abdullah II's reminder will hopefully prompt his Saudi hosts and global Islam to isolate and eradicate the threat of terrorism.

The Khawarij, like ISIS today, claimed to be upholding the laws of God. Imam Ali led the formulation of a consensus against them before fighting them in battle. Building on the Riyadh summit, under the leadership of the Saudi Deputy Crown Prince Mohammed bin Salman, who is committed to combating extremist thought, Muslim governments should now lead in building a new global Muslim consensus.

Bringing political and religious leaders from all 52 Muslim-majority countries to Mecca and agreeing on a Mecca Declaration will result in ijma, or consensus, that is binding on Muslims. The 2004 Amman Message is precedent for this.

To suffocate and end Islamist terrorism, here are the three ideas on which the religious and political leaders in Mecca should focus:

First, Muslims can fully observe Islam without a theocracy, caliphate or Islamic State. Sunni Islam's greatest contemporary authority, Sheikh Abdullah bin Bayyah, has repeatedly highlighted this fact with scriptural evidence. Therefore, it is not a religious obligation to work towards a caliphate, nor is it sinful to live as a Muslim without a caliph.

Second, the West is not at war with Islam, and Islam is not at war with the West. Religious freedom in the West for 30 million Muslims illustrates that Islam and the West are fully compatible. It is in communist China that Muslims cannot fast, grow a beard, name their children Mohamed, or gather to discuss Islam. The West is a domain of freedom for Muslims.

Third, Christians, Jews, disbelievers, atheists and others are free to believe and practice whatever they wish across the world. The Quran confirms that there is no compulsion of faith. In the name of God and jihad, it is forbidden to kill. Those who murder in the name of religion are not martyrs going to heaven but murderers going to hell.