CAB129-36 — Page 137

[C.O.S. (49) 218

21st June, 1949.]

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Page 137

APPENDIX A

CHIEFS OF STAFF COMMITTEE

CHANNEL TUNNEL

APPRECIATION BY THE CHIEFS OF STAFF

In this paper we review, in the light of modern developments, the military implications of a Tunnel under the English Channel.

Existing Proposals

2. We assume that the present proposals for the construction of a Tunnel involve no substantial departure from plans put forward by the Channel Tunnel Company in 1930. These contemplated the construction of a tunnel 36 miles long, of which 24 miles would be under the Straits of Dover. The English

mouth of the tunnel would be about one mile west of Folkestone and the French mouth some ten miles south of Calais. There would be two independent traffic tunnels, of 18 feet 6 inch diameter, each containing a single line of electric railway. There would also be a pilot tunnel of 10 feet diameter for drainage and ventilation. It was estimated in 1930 that the whole project would be completed in 61 to 7 years.

3. The tunnel, if started now, is not likely to be completed before 1957 and would, therefore, have no bearing on our short-term strategy. Once finished, how- ever, it would remain one of the principal peacetime means of communication with the Continent in the forseeable future. Any strategic review of the project must therefore take account of the possibility of a radical change in our present relation- ship with the French Government.

Historical

4. Since 1882 the proposal to build a Channel Tunnel has periodically engaged the attention of His Majesty's Government. On each occasion it has been rejected because, quite apart from political and economic considerations, it has been deemed militarily undesirable. The principal military argument has been the fear that the tunnel would provide a means of invading this country.

5. Early views were exemplified by Lord Wolseley in 1882 when he wrote:--- "The danger is briefly this, that the French, or whoever for the time being held the Calais end of the Tunnel, could by a coup de main seize our end of it, and the very moment they had done so Dover would become a tête du pont for their army, from which they could issue forth with any large army they chose to bring through the Tunnel. In other words, from that moment we should cease to be an independent Power, as we have no army in England, nor could we raise any army that would have the slightest possible. chance, under any circumstances whatever, short of the direct interposition of God Almighty, of enabling us to withstand a French Army of the character that could be poured into this country.'

CC

6. Although military opinion subsequently modified this extreme view of the potential danger to the country's security, the objection was still considered valid enough in 1924 to prohibit the scheme on the grounds that the existence of a Tunnel (particularly in the event of an international crisis) might lead to a public demand for measures, whether of naval, military or air defences, which would tend to concentrate an undue proportion of our limited defensive resources in the region of the Tunnel to the detriment of the genegal 3eme 60 the country.'

Views of the ageƒ3&p Shaff in 1930

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