Geri Haliwell claimed her as the original Spice Girl, but Thatcher would never have deleted a tweet

Geri Halliwell was still warming her milk bottle on the radiator at primary school when Margaret Thatcher moved in to Downing Street. (Hang on a minute, didn't Mrs Thatcher abolish school milk?) Anyway, Ms Halliwell's self-regarding tweet following the death of the former Prime Minister reveals something of the massive cultural change that Britain has undergone since the Thatcher era.

Today, everyone has a voice, everyone can reach an audience, and even a Spice Girl (rtd) must have an unmediated opinion on matters of global importance. "Thinking of our 1st Lady of girl power," she wrote, for the benefit of her 203,000 followers. "Margaret Thatcher, a grocer's daughter who taught me anything is possible...x" Mrs Thatcher had left office six years before the Spice Girls had uttered their first "zig-a-zig-ah", but no matter. I can see how the wannabe Spice Girls might construe themselves as a glamorous manifestation of Thatcherism, especially when dressed up in Union Jack hot pants. But why on earth did Ms Halliwell feel the need to unburden herself of her irrelevant aperçu on the demise of Mrs Thatcher?

As it turns out, she was soon to realise what a bad idea this was. Overwhelmed by the violent reaction of those who didn't concur with her benevolent analysis, she later deleted her tweet, and apologised for causing offence. Girl Power? Give me a break! At the first sign of opposition from the trolls, loonies and losers who populate Twitter, she throws in the towel.

If you're going to share your valuable opinions with the world, girlfriend, you might as well stick with them. Which brings me back to the huge shift in the mechanics of public discourse. I am not seeking to make a crass comparison between Geri Halliwell and Mrs Thatcher, but Mrs T's conviction, on the other hand, was burnished with asbestos. No amount of protest could singe her will. Nevertheless, you could argue that it was easier to do so in those days. Of course, people could take to the streets over the big issues (and they did). There was also the opportunity to register opposition at the ballot box (and we know she won three times). Yet in the pre-Internet, pre-Twitter days, there was no imperative to check, minute by minute, where public opinion was moving, how policies were playing, what was gaining traction and what was not.

Twitter in particular is an extremely powerful medium, and a useful tool with which to gauge the tenor of the national conversation. But as the hapless Geri discovered - and anyone in public life these days is finding - it's hard to resist being influenced when you see a tide of disagreement hurtling towards you through cyberspace. Mrs T never had to worry about this constant noise. ERM is trending! Look at what Geoffrey Howe has just tweeted! The blogosphere is full of stuff on the Belgrano!

They were tough times back then, but life was also a little more straightforward, certainly for politicians. You made your decisions, you got on with the job, and you were judged every five years, and not every nano second. It was the perfect time, you might conclude, for a Prime Minister who didn't believe in consensus politics.