It is declared by a growing number of Christians and non-Christians alike that what is observed in the Islamic State (ISIS, also called Daesh from an Arabic acronym) and other groups that engage in violent jihad does not represent true Islam. This, however, is debatable.
Muhammad did force non-Muslims into submission and made them pay a tax to stay alive. Muhammad did behead captured enemies, or at least ordered such and then observed the process. He did cut off the hands of thieves. He did arrange that captured women and children be sold as slaves. He did permit captured women to be taken as concubines; in fact, his last wife was a beauty he had rescued from a Jewish tribe that the Muslim army had defeated. Muhammad authorized lying if and when the cause of Islam was being defended or advanced. He did practice forced conversions. Whatever Muhammad did in his lifetime, as spelled out in the Qur’an, found in the hadith, or seen in the biography of Muhammad (called the Sira, written by Ibn Ishaq), are being imitated by the Islamic State now. And this Caliphate does not deny but proudly embraces this fact.
Not only do they not deny they are imitating Muhammad’s tactics, but IS would view non-compliance to be at minimum weakness bordering on apostasy. This is the present state of affairs. Muhammad taught that Islam should be global and that Shar’ia Law be universal, which would result in the entire world then being at peace. It is the task of Muslims to bring this about. Anything less than this is un-Islamic.
Then there is Salafism. This term describes Muslims who practice a conservative, even radical form of their faith. They attempt to imitate Muhammad and hope to live under Shar’ia Law. It is just that they cannot do so except in a place where it is politically and culturally possible. “Most Salafis are not jihadists, and most adhere to sects that reject the Islamic State,” writes Graeme Wood in his March, 2015, article in Atlantic entitled, “What ISIS Really Wants.” They might, however, if given the chance, be every bit as strict as violent jihadists. Wood states that Salafis might implement “monstrous practices such as slavery and amputation – but at some future point.” The Salafis’ stated agenda is to purify their personal lives, including personal hygiene, and to be faithful in prayer and observance of all standard forms of the main rituals of Islam. 
Are all those who promote and/or engage in violent jihad real Muslims? If the answer is No, then it must be asked, “How could this be?”
There are many reasons why one would turn to violent jihad other than wanting to live like Muhammad. Is it possible that young men and women living in very poor circumstances, without much of a future, could be recruited into something they would later regret? Perhaps peer pressure overcomes them. Perhaps boredom, hopelessness, or a strong sense of inferiority might trigger the desire for a radical change in living. By means of the Internet, which jihadists use but detest at the same time, they recruit these vulnerable youth.
Not only those who grow up in less-than-ideal circumstances are attracted to violence and murder. It is enough that Muhammad both sanctioned and participated in such. The desire for a wonderful eternal future is a powerful magnet and may be the strongest motivator for a violent defense or advance of Islam.
The Internet also shows clearly what is available in the Western world; could envy be an instigating element that plays on the Muslim mind? Or, might a motivation be a chance for a quick ticket to paradise and seventy-two virgins, which may appear to be the only way to get love? Might young men and women be driven to distraction, to a cultic or toxic state of mind and made willing to do almost anything to lift themselves out of depression and despair?
Since Islam is both religion and state, which predominates? Or is there such a blending that there is no religion or state, just Islam? Islam is yet very much tribally oriented, one tribe against another, which is plain to see in daily news stories. Is the Muslim fighting for Muhammad, the imam, the umma (Muslim community), the political boundary, or what? This question might receive a hundred different answers, and silence as an answer could be expected.
fighters with al-Qaeda, the Taliban, the various Shia and Sunni militias, even
with ISIS, true Muslims? Yes, No, and Maybe! Only God knows.
 By “Personal hygiene” is meant the intent to properly observe and avoid the many ways that Muslims might defile themselves before prayer. A chief instance of this is to avoid splashing oneself with urine in the toilet. Proper techniques for washing feet, arms, hands, and face before prayer is critical in the Muslim mind. This little section could continue for many pages describing the means of coping with and defending against the evil jinn (demons), since hygiene in the Muslim world is not what non-Muslim Westerners understand but is more concerned with superstitions about the supernatural.