In one of the great speeches of the 20th century, General Charles de Gaulle on BBC Radio on June 18,1940 spoke to the French people after the government of France had capitulated to Nazi Germany.  Optimistically, he argued that France would be able in the future to overcome the enemy by a "superior mechanical force."  The fate of the world depended on it.

Hope, de Gaulle said, must not disappear.

Today, the democratic world must respond to the enemy, radical Islam and Islamist terrorism, with the same force and in the same spirit that de Gaulle embodied.  The task has become increasingly difficult and complicated with the changing nature of the threat and the varied massacres and terrorist Islamist attacks.  The West has also now become aware of the sophisticated propaganda machine of the jihadist terrorist groups, especially ISIS, whose propaganda spreads on the internet, Skype, Facebook, YouTube, and satellite outlets.  Now revelations about one intelligence unit, EMNI, responsible for an external terrorist network, of the secret service of ISIS, is the latest cause for Western concern.  

The first organized attack on the West came from groups such as al-Qaeda that concentrated on important or symbolic targets.  Osama bin Laden was responsible for 9/11 and war on U.S., arguing that the U.S. had massacred Muslim people and supported Israel.  To this attack was added the fight against those regimes, including Saudi Arabia, that aided the U.S. 

Then terrorist groups in different countries attacked "soft targets" – train stations and hotels.  More recently, so-called lone wolf jihadists have attacked Jewish museums, night clubs, the promenade of a fashionable seaside resort, in European countries.

It is essential for all defending Western civilization to be aware of the ideology that drives all these different terrorist activities.  The rise of Islamist violence and terrorism has illustrated a clash of cultures in the world, not universal agreement on some hypothetical end of history.  Muslim societies accepting that "the Koran is our Constitution" are antithetical to Western democracies and the secular rule of law.  Glorification of terrorists is incompatible with a system of law and order, however imperfect.  The rise of jihadism stems from an extreme form of Islam, not the revenge of Muslim countries for Western colonialism.

The problem for the West started in the 18th century in the area of Najd in the Arabian Peninsula, when two men met.  One was a religious figure, Abd al-Wahhab, son of an Islamic cleric (juge) who wanted to stop Bedouins from being pagans.  The objective was to return to a "pure" Islam, that of the Prophet and his companions.  This was the extreme, puritanical, and rigid form of Islamist doctrine.  This overlaps with Salafism, which goes back to an even earlier period, the first three generations of Islam, the so-called "Pious  Predecessors."  

In the small town of Diriya, Wahhab in 1744 met Ibn Saud, ruler of the area, and agreed on an arrangement.  This was the pact that involved the lowering of taxes on agricultural products and the raising of revenue by a process of jihad and conquest of neighboring cities on one side and religious extremism on the other.

The alliance of the two men led to conquest of Arabia and the imposition of both centralized administration and the extreme religious point of view on it.  The area gradually changed from continual tribal wars in search of spoils to a political center and a dominant Saudi ruling family, and to Wahhabism, an extreme form of Islam, as the dominant form.

At first, Wahhabism was concerned with defense of Muslim countries against "impurity" within them.  This meant having a military force, a fanatical sect that included mercenaries.  Then grew the emphasis on jihad, the assault of Western systems, that became more urgent with the creation by Hassan al-Banna, a 22-year old teacher, in 1928 in Cairo of the Muslim Brotherhood.

It was the first important movement that tried to unite activist Muslims to affirm an Islamic identity in the face of British and French colonialism.  Therefore, a major objective of Banna was the restoration of the caliphate, a political system that had been abolished by Turkish leader Mustafa Kemal Ataturk in 1924, to rule over Arab countries.  Moreover, that caliphate was to exercise political power, to become politically important, and to reform society.

Parenthetically, Banna was the grandfather of Tariq Ramadan, the Swiss-born academic, often a spokesperson for the Brotherhood and an extreme critic of Israel.  In 2013, he wrote that the overthrow of the Egyptian president, Mohamed Morsi, Brotherhood leader, was orchestrated by a conspiracy of the U.S. and Israel.

Inherent in the position of the Brotherhood is that the Muslim ruler should be destroyed if he contravenes the divine law.  The Brotherhood had tried to assassinate President Gamal Abdel Nasser in October 1954 and succeeded in assassinating President Anwar Sadat on October 6, 1981.

In the 1960s, the Brotherhood became even more extreme with the influence of Sayyid Qutb, who emphasized resort to violence and overthrow of bad Muslim governments.  It was the teaching of Qutb, who was executed in 1966, that led to Sadat's assassination and to continuing jihadism.

For the West, the threat of Salafist jihadist terrorism stems from the Soviet invasion of Afghanistan in 1979.  The opposition to that event was a combination of Saudi and American force, the employment of American money and the CIA, and the recruitment of local fighters by the U.S. and Pakistan.  Motives were different.  The U.S. was engaged in the Cold War with the Soviet Union.  The local fighters were liberating territory of an occupied Muslim country.  The Taliban was born.

Salafists are of various kinds.  Some insist on piety, education, and predication; others are more interested in political and nonviolent reforms.  The third group, advocates of global jihadism, is what affects the West and Muslim countries. 

Starting in the fight against regimes of Algeria and Egypt, jihadism spread to Albania and the Caucasus.  By late 1990s, global jihad against the West was basis of al-Qaeda.  The fall of Saddam Hussein led al-Qaeda to become influential in Iraq.  Organized jihadism then became nihilist, with the creation of ISIS in 2006 and the caliphate in 2013, both jihadist and a territorial state.

Like de Gaulle in 1940 fighting against Nazi Germany, Western leaders, together with Russia, must pluck up courage and fight the evil.  It helps to know who the enemy is.  The next president of the U.S. must fight from the front, not from behind.