Remember the Birmingham Six, the Maguire Seven, the Guildford Four and Judith Ward? Behind the campaigning numbers were 18 innocent people who collectively spent scores of years in British jails after being falsely convicted of terrorism offences.

Their sin was to be Irish (or, in Ward's case, to have spent time in Ireland) during that 1970s period when the Provisional IRA was bombing targets in the UK.

The police, convinced in each case that the 18 were guilty, extracted confessions under torture and/or intimidation, faked evidence and lied in court.

All of this is known, but all of this is too easily forgotten. Now, amid the hue and cry in Britain over the activities of the Islamic State (Isis), it is timely to recall the "mistakes" by the police, by MI5 and by a compliant media, of 40 years ago.

I couldn't help but notice the triumphant and incautious tone in some newspapers last week when five men, aged 20 to 21, were arrested in London over "a suspected terrorist plot to mount an attack in Britain".

We learned from some papers last Wednesday (8 October) that they had links to Syria and to Islamic State (Isis). The headlines were unequivocal: "Jihadi plot to attack UK smashed" (Daily Mail); "MI5 smash British 'Isil terror plot'" (Daily Telegraph); "British medical student arrested on terror charges 'may have just returned from Somalia'" (the Independent); and "MI5 nab surgeon" (The Sun).

Given that the force is not supposed to leak to the press, journalists received a surprising amount of detail in off-the-record briefings. One of the men was named as Tarik Hassane, a 21-year-old medical student, and we learned he had, allegedly, sent a tweet to two friends saying: "Oi lads… I smell war" (giving the Sun a follow-up splash headline on Thursday).

But was that tweet really about the conflict in Syria and Iraq? According to a lengthy article on the Islam21c site, it concerned a personal matter involving women friends of Hassane's friends.

I don't know whether that's true or not, of course. But I am not alone in having suspicions about the case and about the sensationalism of the coverage surrounding his arrest and that of the other four.

Even the Mail began to wonder. Towards the end of its article on Thursday it hedged its bets by reporting that friends of Hassane said his tweet "simply referred to a 'bunch of rowdy girls' who were bickering on the social networking site."

Channel 4 News also reported that claim by Hassane's friends (but I note it did so while revealing the first picture of the student and asserting that he had been originally named by the Sun).

I am heartened that the Guardian's first news report included this key paragraph:

"Some past high-profile terror arrests have been based on intelligence that turned out to be inaccurate, and have led to accusations that police and MI5 have ramped up the nature of possible plots".

Even so, Scotland Yard tell me that the five men remain under arrest because, although the legal questioning period has passed, a warrant granting the police an extension runs until tomorrow (14 October).

So it's possible that we will know much more in 24 hours' time. But I can't help thinking that the errors committed against the Irish in the 1970s are being replayed with a new set of victims, British Muslims, in 2014.

Why is the Sun outraged by attacks on its anti-Isis stance?

Meanwhile, Tim Fenton, in a blogpost on Zelo Street raised a much more interesting matter: the linkage between the MI5 arrests and the Sun's call last Wednesday (8 October) to "Britons of all faiths to unite to defeat IS fanatics".

I wrote at the time that the paper had "used its muscle to make a valid political invention". I stand by that.

However, that claim to validity was immediately questioned by Nesrine Malik, who viewed the Sun's 'Unite against Isis' campaign as "a proxy for anti-Muslim bigotry." In fact, she considered it to be a "stunt" in which...

"Muslims have to prove their British credentials with a display of loyalty – that their Britishness is not taken for granted until they do so. You are a shady Muslim first, and a citizen second... It is a way to sneak into plain sight an increasingly popular view that Muslims are an enemy within, and, as Islamic State allegedly reaches British shores, the idea that British Muslims are their allies."

That did give me pause for thought. I trailed down the 1,500-plus comments thread below Malik's polemic in which, amid the predictable tangential diversions (and plenty of deletions), there was a measure of support for her opinion among the criticism.

I noted that the Sun's managing editor, Stig Abell, thought Malik's comment "vapid, pious and divorced from reality".

I haven't spoken to him about his tweet, but I'm guessing he was angry because - in company with his editor, David Dinsmore - he sincerely believed the paper had made a genuine attempt to do something worthwhile, and then had it thrown back in their faces.

Although I am more open than Malik in accepting that their motives were not as she suggested, Abell's scathing response to her was unworthy of him. It is perfectly plausible to argue that there is a difference between good intentions and unintended consequences.

That difference is simple to grasp. Many Muslims, after years of alienation and what they regard as prejudicial media coverage, are bound to see a sinister agenda in anything done by newspapers they regard, rightly or wrongly, as hostile.

Similarly, the Sun would have done better not to have linked its anti-Isis campaign to what it called a "police swoop on first suspected Islamic State terror cell in UK."

This tended to reaffirm for Muslims living in Britain that they are under collective suspicion unless they distance themselves publicly from Isis.

Surely, Malik's argument required a cogent reply stressing the paper's sincerity rather than an offhand tweet.