We have just passed the 75th anniversary of Mussolini's invasion of Abyssinia. The invasion began on 3 October 1935, prompting pacifists and other campaigners in Britain to call for an arms embargo on Italy.
The arms industry lobbied against this measure. As a result, the UK government rejected the suggestion, and British arms companies continued to sell weapons to Mussolini. In 1940, he took Italy into war with the UK.
Of course, this was neither the first or the last time that ministers allowed the sale of weapons to a regime which later turned against them. US companies were arming the Japanese air force as late as May 1939, while both Saddam Hussein and Osama Bin Laden were famously armed by the West.
This is just one of the reasons why so many people have opposed arms exports. The UK's current Defence Secretary Liam Fox is fond of justifying expenditure on nuclear weapons on the grounds that we don't know what the future holds. By the same logic, he can't know what will happen to the weapons which he allows the arms industry to sell.
British peace activists in the 1930s are popularly portrayed as naïve. It is said that they failed to realise the need to fight fascism. I have heard people reject the anti-arms movement with the rhetorical question, “What would have happened if we'd listened to people like you in the thirties?”. The answer is that fascism may well have been weaker.