The Versailles Treaty's provisions for the destruction of German war-making and military capabilities was a fairly unprecedented step in 1919. The last century had seen military occupation before. There was an Allied army of occupation in northern France after Waterloo and the newly-unified Germany likewise occupied some of the same ground until France paid off her indemnity after the Franco-Prussian War. Likewise the military occupation of the Confederacy sought to disarm Southern armies and restore order. But none of these occupations were of a fully-industrialized polity like Germany and the scale of reducing the wartime German military to Treaty restrictions was quite daunting. The Allied plan to accomplish this task was through a limited occupation force that would work with the German government and maintain an inspection regime.

The main body concerned with disarmament was the Inter-Allied Military Commission of Control (IAMCC). The IAMCC consisted of around 1500 troops and headed by a staff of fifteen officers. Most of the IAMCC's personnel were French, with the UK maintaining a strong presence, followed up by smaller contributions from Belgium, Italy, and Japan. The initial plans for IAMCC called for American troops, but the Senates refusal to ratify the Treaty left the Americans out of this loop. IAMCC inspectors would demand the destruction of war material, fortifications, and ensure that the Germans were not pursuing the development of technology forbidden by the Treaty like aircraft or tanks. IAMCC formed in 1920 and disbanded in 1927.

The results of the IAMCC were somewhat mixed. Although Richard Schuster's monograph on the IAMCC maintains that it did succeed in disarming Germany in the 1920s, reviewers of the book have trenchantly noted that this was a qualified success at best. The Reichswehr certainly fought hard against IAMCC inspection and created a large number of schemes to evade the Treaty and plan for a post-Treaty expansion. The IAMCC managed to win a few issues with the Germans, especially for the destruction of fortifications on Germany's eastern frontiers, but it could not stop the Reichswehr's quite ambitious plans to throw off the Treaty. The inspection regime forced the Reichswehr to look abroad to test new equipment like the USSR or China, and while this was a testimony to the efficacy of some of the IAMCC's efforts, it was hardly a defense of the Treaty.

Part of the problem for the IAMCC was that its components had different priorities for Germany's disarmament. The French and British began to part ways after the IAMCC's initial work in the 1920s. The French envisioned the regimen of inspections and controls to be an ongoing process that kept the Boche down while a number of politicians in the UK saw Germany's initial disarmament as a means to presage a wider disarmament of the European continent. Belgium largely went along with France's lead, but the IAMCC's two smaller powers were arguably more interested in what the Germans could teach them about military science than destroying Germany's military capabilities. Ernst Heinkel's memoirs recall that the Japanese inspectors often gave him advance notice of inspection teams in return for data on the clandestine aircraft he was producing. The Japanese likewise saw German expertise and experience as a vital stepping stone for building up its own submarine force.

The Reichswehr and the German government were often able to play the factions within the IAMCC against each other to prevent a more thorough disarmament of the country. The Allies could threaten an occupation of the country or even a renewal of war. But the massive destabilization of Germany that attended the 1924 occupation of the Ruhr coupled with the rifts this occupation opened in the Allied camp made this something of an empty threat by the mid-1920s. While Allied leaders would not stomach an open abrogation of the Treaty, there was less of a will to enforce all of its provisions within the Allied camp.

German Foreign Minister Gustav Stresemann exploited at Locarno in 1925. IAMCC folded up shop in January 1927 and responsibility for handling the enforcement of the Treaty's clauses on disarmament fell to the League of Nations. Disagreements between the British and French led to the League system being less organized to investigate and inspect German compliance disarmament. The League was never really able to replicate the same system of inspections and controls that characterized the IAMCC period. The Death of Marshal Foch denied France a powerful voice in favor of Germany's permanent disarmament and the League's enforcement of the Treaty languished.

The Versailles systems for disarmament were something of an open door for the Germans to push against. While IAMCC could prevent concrete and actual rearmament, it never could stop planning for rearmament. The Reichswehr's shadow rearmament was occasionally foiled by IAMCC, but never fully arrested by it. In hindsight, the IAMCC was both too powerful and too weak. Its presence was fodder to German nationalists who carped on the unfair punishments of the Treaty. This hindered the development of closer cooperation between the Allies and the Republic. There was a not insignificant percentage of the Weimar public that was disenchanted with war and the expense of militarism; the public debates over the Panzerschiffe were quite fierce and the German press exposes of clandestine rearmament were widely-read in the left-wing press. But while the IAMCC inspectorates may have made political rapprochement on disarmament more difficult, it was also too weak to be supported indefinitely. The differing strategic goals of the UK and France proved to be a wedge that prevented a consensus to develop on what to do should Germany elect to trash the Treaty and rearm. The prime beneficiary of Allied disunity was Hitler who was able to exploit the anemic controls of the Treaty to pursue a reckless rearmament scheme that dwarfed even the most ambitious plans of the Reichswehr.

Sources

Corum, James S. The Roots of Blitzkrieg: Hans Von Seeckt and German Military Reform. Lawrence: University Press of Kansas, 1992.

Fox, John P. "Britain and the Inter-Allied Military Commission of Control, 1925-26." Journal of Contemporary History 4, no. 2 (1969): 143-164.

Shuster, Richard J. German Disarmament After World War I: The Diplomacy of International Arms Inspection, 1920-1931. London: Routledge, 2012.