After an off-and-on 200-year struggle for control of the Holy Land, in 1291 the conflict ended in failure with the fall of the last Christian stronghold at Acre. And that was the end of it - thousands of lives lost for nothing.
In the past century Western fears turned to the creeping of communism into Asia and set out to put that to a stop. It failed. But in the meantime scores of New Zealanders died.
A total of 5000 Kiwi soldiers served in Korea, 33 were killed in action and 79 wounded.
The war ended in a draw and the demarcation zone remains the most tender of spots.
In Vietnam a total of 3,890 New Zealand military volunteers served between June 1964 and December 1972. Thirty-seven were killed and 187 wounded. The war was a total loss and communism flourishes still.
Then came Afghanistan where 10 New Zealand Defence Force soldiers have died, most while carrying out their duties as part of the Provincial Reconstruction Team. Yet
Afghanistan remains a festering sore and, left to itself, will revert to its age-old, thuggish feudalism - no matter how hard the West tries to stop it.
It is the Afghan experience that makes me fear for the few military personnel we have already sent to Iraq. They might be seen by the allies as non-combatants, but certainly not by the Muslim fundamentalists.
The non-combatant reconstruction teams in Afghanistan were targets just because they were there, and I suspect that the troops we have sent to Iraq will be, too.
We can only pray that none of the trainers we have sent, and who are kept heavily protected "behind the wire", is gunned down by one of their trainees. It's been known to happen in that benighted land.
The even more sinister aspect of this whole business is the spread of maniacal Muslim fanaticism to this country, Australia, Britain, Canada and others. Mr Key is to be congratulated for beefing up our security laws and services to cope with this threat.
Mr Key says Government agencies have a watch list of between 30 and 40 people of concern in the "foreign fighter" context, and another 30 or 40 under further investigation.
He said five New Zealand citizens or residents were known to be fighting in Syria but the number could be larger because dual citizens or New Zealanders could have left from other countries.
I suppose these are the same sort of people who join gangs in this country and have decided that the Islamic State is a far more exciting gang than, say, the Mongrel Mob or Black Power.
After all, Isis will put guns or bombs in their hands and tell them to kill people.
So what do we do? The West should simply pull right out of the area altogether and leave it to the natives to sort themselves out - or not.
Ah, but what about oil?
garth.george@hotmail.com
Garth George is a veteran newspaper journalist, retired and living in Rotorua.