Here's the thing about Twitter – it allows you to say anything you like and it also punishes you for saying anything you like. You're caught somewhere between absolute freedom and absolute condemnation.
One false move – or, rather, one stupid, or offensive, tweet – and, by the law of the Twitter mob, you're toast.
Take the case of Northern Ireland-born footballer Shane Duffy. The 21-year-old Everton defender, who chose to play for the Republic of Ireland, has been ritually lambasted after a pro-IRA comment appeared on his Twitter page.
Duffy denies posting the message – which, rather unimaginatively, stated "Up the Ra!" – on his account during the St Patrick's Day celebrations.
Since the incident, the original tweet, which came from a fan, has been removed from Duffy's timeline. He later apologised for the updates, writing (and I quote): "sorry everyone some little paddy had my phone last night tweets wernt me ... sorry if it offended anyone!! cant leave ur phone anywhere now!!"
But it was too late. The inevitable tsunami of condemnation had already begun and soon Duffy was swamped with 40 shades of semi-literate abuse, accused (among other, less-printable, epithets) of being a "terrorist-supporting scumbag" and "promoting baby killers".
Let's leave aside the question over whether Duffy's phrase "some little paddy" is in itself unacceptable (we don't want another Twitter storm) and concentrate on the facts.
Here's the official account from Everton FC: "Shane was on an evening out when his phone was taken by someone, who then retweeted an offensive remark, for which Shane has this morning publicly apologised for."
Regardless of who's responsible, most of us can agree that bleating "Up the Ra!", accompanied by a picture of a pint of Guinness, is a dumb, inappropriate and ridiculously offensive way to celebrate our national saint's day.
But, equally, let's not act as though the sky is about to fall in. As ever, in these ridiculous social media rows, the abuse dished out in response is just as nasty, if not more so, than the original comment.
In short, it's pretty unedifying all round: a big, noisy, pointless fight where no one comes out looking good.
And that's the trouble with Twitter. Anyone who's young, drunk, or stupid – or, worse, all three – should stay well away from it. All the more so if they happen to be in the public eye.
Because one foolish tweet has the power, at least potentially, to undermine their whole career. At two o'clock in the morning, out on a bender with their mates, it might feel fun and easy to post some rubbish that they'd prefer to forget in the morning.
But, on social media, there's always someone watching, at whatever hour of the day, or night. Possibly someone bitter and jealous, just waiting for the moment to strike.
Once the self-righteous orgy of outrage starts, there's no way of stopping it, as Duffy has found to his cost. Reacting to the outrage, he tweeted: "Wow so much hate on something I didn't do ... Fair enough gotta take it because its my twitter. And again it was not me who tweeted ... And retweeted loads last night! Really am sorry if it offended anyone.. Sorry guys!"
I can't help feeling sorry for the young man. He has been vilified and castigated out of all proportion to his supposed 'crime', which in any case he denies.
The original comment was indeed crass and unpleasant. But it seems that nobody is allowed to make any mistakes these days, especially not on Twitter.
If you do, you'll never be allowed to forget about it. Whether innocent or guilty, Shane Duffy would be best advised to treat Twitter like a very dangerous drug – to be used sparingly and with caution. Or, better still, not at all.