There have been many terror attacks on civilians in western cities since the 21st century began.
The regularity of the atrocities has bred a degree of determination to try to continue normal life.
Even so, Monday’s massacre has caused particular anguish and horror because the target was not only a concert, but a crowd of people many of whom were children.
This is as depraved as human behaviour gets.
Islamic State (IS) has claimed responsibility for the carnage in Manchester Arena when Salman Abedi blew himself up at the event by the pop star Ariana Grande. IS confirms its reputation as one of the most barbarous groups in modern history.
Prime Minister Theresa May and others have spoken eloquently about the uplifting way in which people helped victims at the scene, and the fine work of emergency teams.
Mrs May said that the terrorists will not change our values. This is true – if they think they can change an entire way of living and thinking of the continent of Europe, they are deluded.
The threat from radical Islam is a global challenge but at present the number of attacks remains low in proportion to the populations of the targeted countries. Many times more people are dying on the roads in Britain than in terrorism, where the most recent terrorist attack was at Westminster in March, but the last large-scale attack was in July 2005. Even so there is a future risk from terror gangs getting weapons of mass destruction. The intelligence services, who are central to the fight against Islamic extremists and who helped defeat IRA terror, will need generous funding in the decades ahead.
We need major help from British Muslims to defeat a small but ruthless minority in their midst. We also need to insist that immigrants conform to core values of the country, the UK, that is generously giving them a home. These include a shared acceptance of basic rights, democracy and non violence. If such a stipulation is unacceptable, then would-be immigrants are free to seek entry to another country.
Finally, when we say terror will never pay, we must ensure that is so – unlike what happened in Northern Ireland.