Better late than never. The Czech authorities are binning Russia’s bid for a nuclear power contract and expelling 18 embassy officials in connection with a fatal explosion seven years ago.

According to Czech officials and the Respekt newsweekly, two Russians blamed for a failed assassination in Britain in 2018, and for a hit on a Bulgarian arms dealer in 2015, are wanted in connection for an act of state terrorism against the Czech Republic.

Some clarity is welcome. The incident in October 2014 at the Vrbětice arms depot was forgotten with great alacrity. A huge explosion of 50 tonnes of munitions killed two workers. Another big blast followed in December. The facility was state-owned, but, in an arrangement of characteristic post-communist Czech opacity, privately managed. Security was sloppy. The clean-up costs were huge, but compensation to nearby residents stingy.

The investigation was lethargic and inconclusive. It should have drawn a connection with Russian activities in the Czech Republic. Tight ties in business, finance, and the energy sector are notorious, often between people with common communist-era roots or family ties. The weapons destroyed in the blast were heading to Ukraine, which was struggling to defend itself against Russian invasion. (The sabotage went wrong, Czech police say: the shipment was meant to blow up later.)

The Czech counter-intelligence service, BIS, regularly highlights the threat from Russian spookdom in its unclassified annual reports. It has also warned about Rosatom’s tender for the €6bn ($7.27bn) contract to build a new unit at the Dukovany power plant. But the political will to follow up on the spy catcher’s warnings has been lacking.

Only when allied services (mostly American or British) intervene does anything happen. That seems to be the case this time. Someone tipped off the Czech authorities that two Russian spies, known for their later involvement in the Salisbury nerve-agent attack, visited the arms depot in the days leading up to the explosion. They entered the country under false names, gaining access to the depot with a cover story about working for the Tajik national guard. In fact, they work for Unit 29155, the assassination and sabotage specialists at Russia’s military intelligence service, usually known as the GRU. The Bulgarian authorities want to question them for the attempted murder of the arms dealer, Emilian Gebrev — who just happened to have sold the Czech weapons to Ukraine.

The expulsions are welcome, but will remove only a sliver of the staff at Russia’s outsize embassy in Prague and its consulate in Karlovy Vary. Both, incidentally, are mainly involved in spying on Germany.

Russia will doubtless retaliate. It may also maintain that the two men, whose real names are Aleksandr Mishkin and Anatoly Chepiga, were simply keen to visit the shoemaking museum in the nearby light-industrial city of Zlín. That will be as plausible as their claim that an interest in church architecture took them to the English cathedral city of Salisbury, not the near lethal poisoning of Sergei Skripal (a retired Russian spy for British intelligence) and his daughter Julia.

The timing is puzzling. Why did it take so long to join the dots? Bellingcat’s open-source investigators uncovered the identities of the sinister duo — and many of their colleagues — nearly a year ago. The most likely explanation is that the Biden administration bumped the Czechs into acting, as part of its efforts to raise international pressure on the Kremlin.

The big question now is how many other European countries will deal similarly seriously with the Putin regime, expelling spies and canceling contracts. Without France and Germany on board, little will change. And while Europe dithers, Ukrainians die.