Britain had a secret plan to blow up the Channel Tunnel with an atomic bomb in case of Soviet invasion from France, documents from the National Archive reveal.
As the vision for the connecting tunnel between Folkestone and Calais became more concrete, Ministry of Defence (MoD) civil servants and senior military officers drew up the nuclear plan in order to thwart a possible invasion by the Soviet army from Calais, The Independent has discovered.
The plan, first referenced in 1959, made clear it had to be destroyed by a nuclear bomb because the architecture of the tunnel would prevent a less catastrophic explosion from causing irrevocable damage.
The biggest concerns surrounding the proposal seemed to have been the cost of the action (as a whole new bomb would have had to be built) and its secrecy.
The UK government did not want the French to find out since it thought that “overt preparations to … destroy our only link with France and the remainder of the Continent” would not reflect well on the UK at a time when it was trying to become part of the common market and trying “to convince continental Europe that we have shed forever our island mindedness.”
The report mentions that the explosion would have caused significant flooding in Kent, but that the nuclear option would be “100 per cent effective” at ensuring “totally irreversible total collapse, rupture [of] tunnel and seabed to cause total flooding and complete collapse of part of tunnel.”
The first reference to that extreme plan was made in 1959 when the MoD warned that nuclear weapons had rendered the tunnel vulnerable but that it also provided the UK with a good option in terms of defence.
In 1974, MoD official Michael Legge highlighted some problems with the plan though, saying that the atomic bomb drop could turn the tunnel into a 30-mile-long “mortar firing nuclear explosives out of both ends,” which could cause widespread damage at the entrances of the tunnel.
Legge also pointed out that spending substantial amounts of money on one weapon might not be justified, because if the Soviet tanks got as far as Calais “without a strategic nuclear exchange having occurred, then I think the Channel Tunnel will be an irrelevance.”
Although the atomic bomb option was long considered, the UK government changed its mind. In June 1974, Legge concluded in a letter that the destruction of the tunnel might work best by “creating blockages by head-on train crashes” or by simply flooding it.
The cost of building a bomb and the risk of damaging Kent with a nuclear explosion appeared to outweigh the benefits, The Independent reported. In any case, construction did not begin on the tunnel until 1988, opening to the public four years later.
Read the whole Independent report here.
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