The Guardian reports that Britain's Ministry of Defence softened its stance on the construction of a Channel Tunnel in 1955. By 1959, they had a plan to blow it up with nuclear weapons to prevent an invasion if needed, according to The Independent. Then in 1964, the French government officially lent its support to the idea of a tunnel. Still, it was not until the 1980s that British prime minister Margaret Thatcher and French president François Mitterrand made a concrete agreement to build the Channel Tunnel.
Thatcher wanted the tunnel to be a roadway for passenger cars since, to her, cars represented freedom and individualism. However, Mitterrand was in support of a rail tunnel, since France had much more of a rail culture than Britain. In the end, Thatcher agreed to the railway concept. It seems that the technical issue of ventilation for the exhaust from thousands of car was too challenging and expensive when compared to a rail option, which did not have the same level of pollutants.
However, Thatcher did manage to get two concessions. First, trains would run on the left-hand side. More importantly, the Channel Tunnel would not be supported with public funds. The only public investment was that the British and French rail systems both agreed they would use the tunnel. On January 20, 1986, at Lille, France, Thatcher and Mitterrand announced that Eurotunnel-Transmanche was awarded the Channel Tunnel contract.
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