Prison staff urgently need to be trained to combat radicalisation and prison gangs need to be severely dealt with.
The director of Royal United Services Institute (Rusi) warned a series of successful police operations have turned prisons into "universities of terror".
He said security services may look back at the last eight years as a "golden age of counter terrorism" marked by success and good luck.
Mr Clarke said: "The phenomenon will not wither away in the near future: it is likely to be generational.
"All the available evidence is that radicalisation of alienated Muslim youth in the UK can taken place very rapidly as long as it is based somewhere on personal contact."
Mr Clarke said the evolution of recruitment and terrorist techniques of British cells is "entirely possible" as they learn from their mistakes.
He added: "Most of the plotters have left behind a trail of forensics behind that has led some police professionals to predict that this will seem like a golden age of counter terrorism, when we were both successful and lucky."
Saturday, 13 June 2009
UK Prisons are "universities of terror"
So says Professor Michael Clarke at The Independent.