In identifying those trying to kill us, we should choose our words carefully

What should we call the people who want to kill us? Islamofascists? Islamists? Jihadists? Or just plain murderers? You might say it doesn't matter that much; the point is to stop them. But finding the right words is part of stopping them. It means we've correctly identified our real enemies. It also means we don't unnecessarily create new enemies by making all Muslims feel that they're being treated as terrorists.Take, for comparison, the last major terrorist threat we faced in Britain. Clearly it made a huge difference whether we described the people bent on blowing us up as "the Irish", "Catholics", "Irish Republicans", "Catholic terrorists", "nationalist extremists", "the Provos" or simply "the IRA". On the whole, and fortunately, we stuck with "the IRA". That helped us to win, after a long struggle. In this case, it's not so simple. "Al-Qaida" won't do as the functional equivalent of "the IRA" - not on its own anyway. We need a wider term to describe the kind of violent extremists who perpetrated the London and Madrid bombings. Counter-terrorism experts talk carefully of "al-Qaida-inspired" violence, but that's too complicated for everyday use, as are alternative suggestions such as "violent Muslim extremists" or "modern Islamic militancy". We need a simpler shorthand.

So how about "Islamofascists"? There are some very suggestive resemblances between the mentality and life-paths of self-styled fascists of Europe's bloody 20th century and those of the evil men who have bloodied the beginning of Europe's 21st century. Perhaps the most important common feature is the aestheticisation of violence and the cult of heroic death - the Heldentod. Add to the brew a profoundly ambiguous attitude to modernity; a yearning to overcome what is felt to be the historical humiliation of your country or civilisation; festering anti-semitism; a particular appeal to young, socially and sexually frustrated men; and you have a strong case.

However, the arguments against settling on this tag are stronger. First of all, in the last 50 years the label "fascism" and "fascists" has been profligately over-used and hollowed-out to mean little more than "something the left hates at the moment". If it's bad, and you're on the left, you call it "fascist"; if it's fascist, it feels good to be against it. The list of things described by people on the left as "fascist" over the last half-century would fill several pages, and certainly include Margaret Thatcher, the United States, the Federal Republic of Germany, capitalism, men (aka male chauvinists) and the Daily Mail.

Early 20th-century fascists called themselves fascists. They knew who they were and we knew who they were. To be an anti-fascist in 1938 was to fight Hitler, Mussolini and Franco. Today's "Islamofascists" do not identify themselves as such and it is unclear who exactly is included.

In the form "Islamofascism", and with the added spice of references to "totalitarianism", the label elides two things that need to be kept separate. One is the mentality of death-seeking and death-delivering fanatics. The other is a totalitarian political system that controls major states. This is, if you will, the difference between 1921 in Europe and 1938, when fascism controlled Germany, Italy and Spain.

Now, if nuclear-armed Pakistan and oil-rich Saudi Arabia fall the wrong way, we could be there sooner than we think - but at the moment the only serious contender for the title of Islamic-fascist state is the Islamic Republic of Iran. One of Iran's leading dissidents, Akbar Ganji, has just written an interesting article in Newsweek discussing the application of the label to Iran. Ganji speaks with the unique authority of a man who did time in the ayatollahs' prisons for suggesting that elements in Iran's regime were trying to organise it "along fascist lines". But, he writes, "Iran's political system is very different from that of a totalitarian fascist state". Yes, "warnings about fascist readings of religion can sensitise us to the dangers posed by an organised clerical minority within the Iranian state ... But when leaders like Bush and Blair speak about 'Islamic fascism', many Iranians view it as nothing more than an attempt to prepare public opinion for war."

If "Islamofascists" doesn't work, what about "Islamists"? Islamism, unlike Islamofascism, is a term accepted by all serious analysts of the Islamic world and by many Islamists themselves. It refers, broadly speaking, to Islam recast during the decades since the collapse of the Ottoman empire as a political ideology, a proposed organising principle for state and society. In this sense, we talk of Islamist parties - in government in Turkey, contesting elections in Morocco, officially banned yet massively organised as the Muslim Brotherhood in Egypt. But precisely for that reason, to use the label "Islamists" for the people who are plotting to kill us obscures an important distinction.

Most Islamic terrorists are, in some sense, Islamists, but most Islamists are not terrorists. They are reactionaries. They propose a profoundly conservative religious vision of society which, in its attitudes to free speech, apostasy, homosexuality and women, is generally anathema to secular liberal convictions (including, emphatically, my own). But for the most part they do so through peaceful political means, not through violence. At the most moderate end of the broad spectrum of political Islamism, as represented by Prime Minister Recep Tayyip Erdogan's Justice and Development party in the secular state of Turkey, they are closer to the Christian religious right in the US (for many of whom homosexuality is a sin and abortion is murder) than they are to al-Qaida. For us secular liberals, this religious reaction is also a very bad thing, to be combated with all the peaceful means at our disposal, but it is a different thing - and we make a mistake if we blur the distinction.

So what should we call the suicide mass murderers and would-be mass murderers? The best answer I have found so far is "jihadists", especially in the form "jihadist extremists" or "jihadist terrorists". I know that "jihad" can also be construed as peaceful spiritual struggle, but the Muslim opinion-leaders that I have consulted seem ready to accept this usage. It places a clear demarcation line between ordinary Muslims, and even non-violent political Islamists, on the one hand, and the dealers in death on the other - yet it does not obscure the connection to their religion. In fact, it makes it clearer than either of the alternative terms. Jihad, holy war, is precisely what the suicide bombers tell us - in their pre-murder valedictory messages - that they were proudly engaged upon.

These are the people who are out to kill us and tear apart the civil fabric of our societies. When I say "us", I don't just mean secular liberals or Christians; I mean equally the innocent Muslim citizens whom they murder in the same blasts and whose acceptance in the wider society they jeopardise. Two obligations follow. There is an obligation on those of us who are non-Muslims living in open societies like Britain, to choose our words carefully. Until someone comes up with a better one, I think "jihadists" is the most appropriate shorthand. There is, however, an equal and matching obligation on our Muslim opinion leaders. That is to condemn, audibly and unambiguously, the jihadists who threaten us all.

Timothy Garton Ash