This was stated by 56 per cent of respondents to a security survey published on Wednesday by the Centre for Strategy and Senior Leadership.
The second highest threat is North Korea, cited by 45 per cent, followed by Turkey on 42 per cent and Russia on 41 per cent, according to the survey’s results.
A clear majority, 62 per cent, see the behaviour of certain heads of state as the greatest threat to world stability, even ahead of military conflicts – said by 52 per cent – and climate change, with 43 per cent.
People are most worried about long-term care and dementia, with 40 per cent saying they were very concerned. Just over one in three people worry about the threat of poverty in old age and life-threatening diseases such as cancer.
Accordingly, a clear majority wants the state to spend more money on these issues: specifically for health care, cited by 70 per cent, family support, 69 per cent, and pensions, 65 per cent.
In education too, 76 per cent want schools to be better equipped.
Nearly every third person is also very worried about terrorist attacks, but this fear has steadily declined since a rise in 2016 following Islamist attacks in Europe.
The Allensbach Institue for Public Opinion Research carried out the survey of 1,249 people between January 5 and 17 on behalf of the Centre for Strategy and Senior Leadership.