National Insurance is not insurance

For some reason this has been increasingly irritating of late. Let's just recap how National Insurance works:

• People who earn more, pay more;
• People who have saved more and end up requiring state support, receive less (means-tested benefits);
• People in lower-earning jobs who have higher risk of joblessness, pay less;
• The Government contributes on behalf of groups of people who are not earning (e.g. stay-at-home moms);
• Everyone receives the same state medical care, regardless of NI contributions;
• Substantial contributions are required from employers, who receive not a penny of benefit;
• The permanent jobless, who have never paid premiums, are some of the primary beneficiaries.

Please, could someone tell me in what way this is "insurance"?

I'd feel a lot better if the Government would just come out and admit that this is simply additional income tax plus employer tax and amend the tax scales accordingly. But perhaps the sharp shift in the income tax rates and bands would make things a little bit too obvious for the comfort of the Civil Service.