The League of Nations lacked an armed force of its own and depended on the Great Powers to enforce its resolutions, which they were very unwilling to do. Its two most important members, Britain and France, were reluctant to use sanctions and even more reluctant to resort to military action on behalf of the League. Immediately after the First World War, pacifism became a strong force among both the people and governments of the two countries. The British Conservatives were especially tepid to the League and preferred, when in government, to negotiate treaties without the involvement of that organisation. Moreover, the League's advocacy of disarmament for Britain, France, and its other members, while at the same time advocating collective security, meant that the League was depriving itself of the only forceful means by which it could uphold its authority.