Quite so. And one issue that's forgotten in the comparison with other European states is that most have some form of written constitution or compact that spells out in more or less detail what the relationship between state and citizen is.
In the UK, there is none.
Nothing stops the UK government doing anything it wants - apart perhaps from the European Court of Human Rights, to whose charters the UK signed up, yet it remains among the worst offenders when it comes to the numbers of cases taken to and upheld by said COHR...so it's hardly surprising that people get pretty damned antsy about a central database policed via ID cards....