How many?
... in the World?: There are estimated to be between 0.7 billion (700,000,000) to 1.9 billion (1,900,000,000) Muslims in the world. This is 25% of the world's population - 1 in 4.
...in the United States?: There are estimated to be around 9.9 million (9,900,000); about 3.75 % of the total US population.
(see data below - scroll down).
How many of these Muslims are "Jihadis?"
This is a tricky question. See also "Moderate" Muslim.
Estimates average around 7% of the worlds Islamic population are engaged in some active form of terror activity, in some sort of active support, planning or implementing mode. 7% seems like a relatively small proportion. However, assuming a moderate estimate of 1.5 billion Muslims, even 5% would be what?
5% of 1.5 billion = "only" 75 million (75,000,000) are actvely involved in some phase of violent Jihad.
Surveys have shown that an average of 25% of the Islamic population supports or condone some form of violent jihad. And these are just the ones who admit to it.
25% of 1.5 billion = "only" 375 million (375,000,000)
The only thing keeping US Muslims from more overtly supporting Jihadi violence is their minority status in this nation. As their numbers or concentrations in urban areas increase, you will see more overtly violent activity. (See also "Moderate" Muslims.)
Does it matter how many "peace-loving" Muslims there are if they are all led by or beholden to radical leaders? Here is an interesting perspective comparing how the few (a relative term - in the case of Islam, "few" could mean a few million) activists of movements throughout history can wreak havoc on the world.
How many are working toward Sharia Law in the United States?
This is an even more significant question. Why? Because "stealth" Jihad, or political Islam which some call "Islamism," is more effective than violent Jihad in a liberty embracing country like the US. The numbers? An uneducated guess would be well over 50% of Muslims in the US. I would like informed sources to advise on this point. One doesn't necessarily have to be a Jihadi to be working toward Sharia Law and the domination of US culture by Islamic norms. This is the subject of Robert Spencer's book, Stealth Jihad.
How do we know how many "radical Muslims" there are?
The problem is, we really don't know. I've provided several estimates within this web site ranging from 7 to 25% as shown above on this page. I've been asked by serveral people what the source of my information is. Here is the answer I've provided:
The short answer is this:
Where I've provided numbers on the web site, I've provided underlined links in many cases - e.g. to Pew Research. Where links are not provided, estimates are based on Islamic doctrine, Islamic history, and current events concerning Islamic populations.
The longer and more important answer is this:
First, it depends on how "radical Islam" is defined. Here's how I define radical Islam based on 10 years of observation and study: Muslims the media calls "radicals" are the militant arm of Islam, aka violent jihadis - for example ISIS, al Qaeda etc. and their known sympathizers and supporters. Muslims the media calls "moderates" for the most part do not show themselves to support radicals, but many are likely to have sympathies for radicals by privately supporting them politically, financially, logistically, or socially.
There are survey's done asking this question in the US, such as this one. But how accurate can they be when Islam promotes deception through its doctrine of taqiyya?
Consequently there is some unknown number of what the media calls "moderate" Muslims who are apostate. Zudhi Jasser is one such Muslim. To defend his beliefs, he has to disregard 60% of the Islamic trilogy, including much of the Qur'an. Google "Political Islam" to see the percentage of the Islamic texts that support hatred of the infidel, kafir, Jews, or support for various acts of violent jihad. Many punishments imposed by Sharia are themselves a form of violent jihad if measured by Western sensibilities.
It is impossible to know exact numbers because a key doctrine in orthodox Islam is taqiyya, lying and deception (aka dissimulation) to mislead others, hide true intent, in order to defend the individual Muslim or Islam. Many who appear to be "moderates" turn out to be "radicals" after all. Jihad in the cause of Islam can take many forms to advance Islam: The practice of politics, finance, propaganda, as well as physical violence and acts of terror. So there could be "violent jihadis" (the throat slitting, shooting, or bomb triggering kind), "financial jihadis" (financing violent jihadi efforts), "political jihad" (promoting so-called "hate speech" legislation prohibiting people warning with the truth about Islam) etc. ad nauseum. It is likely that many of those we perceive as "moderates" practice one or more of these types of jihad.
Nobody has the exact number of Muslims who are radical because radicalism can be hidden. Islam is both radical and moderate. Our imperfect measure of "radical" or "moderate" is how a Muslim is perceived, not necessarily what he really believes. "Radical" and "moderate" are both the same "Islam." Which one a particular Muslim appears to be at any point in time depends on his degree of devoutness (the more devout, the more he supports militancy or becomes militant) and the degree he successfullly hides his love for militancy or violent jihad.
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The Data and sources...
Here are several estimates made by a number of organizations...
Number of Muslims in the world (from ReligiousTolerance.org):
Estimates of the total number of Muslims in the world vary greatly:
A more up to date number is 1.9 billion from Islamic Web.com.
Number of Muslims in the U.S.
Nobody knows with certainty.
This is a political hot-potato. Some Muslims have issued inflated numbers to aggrandize their presence. In some instances Muslims may "understate" their numbers to enhance their stealth in a society. Some non-Muslims have accused Muslims of exaggerating their numbers to obtain more political clout. Some Muslims have accused non-Muslims of releasing false, low numbers in order to "marginalize" Islam. Taqiyya does not help.
Estimates of the number of Muslims in North America range from a little over one million adults to seven million adults and children.
One cause of the disagreement appears to be related to the percentage of Muslim immigrants:
Who have abandoned Islam since they arrived in the US, or
Who still consider themselves to be Muslims, but who do not participate in mosque activities.
Estimates include:
President Obama claims "the United States is a Muslim nation". What? With a Muslim population of only 3.75% of the total? See here and here. Most web sites claim about 9 million Muslims in the US. The fact is, there are 23 nations that have larger Muslim populations. And over 90% have larger proportions of Muslims. Was President Obama distorting the facts to help garner goodwill in advance of his "apology tour" to Islamic nations? The facts seem to allude him quite often possibly because he is a great admirer of the Islamic ideology and culture. See Taqiyya.