It found that 65 per cent of Germans, 52 per cent of Spanish and 50 per cent of Italians would intervene if they saw a group of 14-year-olds vandalising a bus shelter, compared to 34 per cent of people in the UK.

Nick Pearce, IPPR director, said: “Adults tend to turn a blind eye or cross the road rather than intervene to discipline another person’s child, often because they fear they might be attacked.”

Julia Margo, an academic who carried out the research, said: “Anti-social behaviour happens when people can’t communicate or control themselves, and a fear of children is a consequence of this and adult society in the 21st century being at a point where we are not raising children properly.”

Wearing hoodies and meeting friends on streets is all part of growing up according to Pam Hibbert, principal policy officer for children’s charity Barnardos.

She said: “We have become fearful of all children. We know for example young crime has remained fairly static in the last 10 years - it is a minority that cause problems. It is the demonisation of children and young people in some sections of the media, and when politicians refer to youngsters as yobs, that breeds the fear.”

Stephen Dainty, headteacher of St Joseph’s school in Birkenhead, Cheshire, however backed the fears reflected in the think tank’s study. He said:

“When teachers confront youths behaving anti-socially, they always fear the consequences and that is why they often think twice about saying something.

There is a genuine lack of respect from youngsters. A lot of them believe they are untouchable so adults are impotent to deal with the situation.”

But Brian Lightman, headteacher at St Cyres school in Glamorgan, said: “I don’t think children are any different to how they used to be. The media tends to focus on the small percentage of youngsters who walk round in hoodies and carry knives. Therefore, adults are scared of them. It is different for teachers who work with them on a daily basis.”