It emerged last week that an IDF reservist who fought in Gaza last year was detained at the UK border last month, on suspicion of war crimes.

The man, who was thought to have been named on an IDF blacklist, was released several hours later, with an apology from the UK after officers realised it wasn’t him. Still, the matter is concerning, and raises several questions. It also has a possible local impact, since British Jews also serve in the IDF.

So, what is this “blacklist”? Who is on it? Who is pushing for the soldiers’ arrest? What can be done about it? And what would have happened had this soldier turned out to be on the list?

We tried to find out, but were met with a wall of silence. We tried the Foreign Office, the Home Office, the embassy, the activists, even the crazy guy on the bus.

No one’s talking. Everyone just wants the story to go away. There have been problems with Israelis entering the UK in the past, but this tended to be politically-motivated stunts targeting high-profile figures such as prime ministers and generals.

Now, it seems, anybody involved with the fighting runs the risk of being detained at the border.

Israelis fairly say this is harassment based on their nationality and ethnicity. There is a legal basis to it, however.

While states don’t usually arrest foreign nationals for allegations of crimes committed abroad, universal jurisdiction (UP), which covers things such as war crimes, is an exception to the rule.

Things may be clearer once the International Criminal Court concludes its investigations.

Until then, it seems that the guidance to IDF personnel will unfortunately stay the same: don’t go telling the world that you’re working in the Israeli military.