Germany was not supposed to have a Ministry of War again. In 1945 the institution had been disbanded, the Wehrmacht dissolved, and the country occupied. Then the Korean War broke out in 1950 and the United States began pressing Konrad Adenauer for a West German contribution to Western European defence. Adenauer agreed, but the public did not. Rearmament — Wiederbewaffnung — was hugely controversial and technically contradicted the Allied occupation statute. So the chancellor set up a special representative, Theodor Blank, with a quietly named bureau in Bonn that everyone called Amt Blank. Officially it did not exist. By 1955 it had over 1,300 employees. On 7 June 1955 the fiction ended and Amt Blank became the Bundesministerium für Verteidigung. The Bundeswehr was founded. Germany joined NATO the same year. Within a year, conscription was back.

The first home of the new ministry was the Ermekeil barracks, an old garrison building down in the city. By the late 1950s it was bursting. The decision was made to build a fresh complex on the Hardthöhe, the wooded hill on Bonn's western outskirts. The Hardthöhe blocks went up at the start of the 1960s and have grown by accretion ever since: more office buildings, an officers' mess, training rooms, a heliport, hardened communications facilities. About 2,000 people work in the ministerial offices alone, with thousands more across the wider Hardthöhe site. The complex is, by the standards of German defence ministries, deliberately understated — no soaring atrium, no monument. The Bonn Republic's instinct, as elsewhere, was to make the institutions of military power look as much like accounting offices as possible.

After reunification the ministry acquired a second seat in Berlin: the Bendlerblock, on the Landwehrkanal in Tiergarten. The name has gravity. It was here that the Ministry of the Reichswehr sat from 1919, here that the Wehrmacht ran the war from 1935 to 1945, and here, on the night of 20 July 1944, that Claus von Stauffenberg and his fellow conspirators were arrested and shot in the courtyard after the failed plot to assassinate Hitler. Today there is a memorial in that courtyard and the building functions as the ministry's Berlin office — used so often by ministers that journalists still write 'the Bendlerblock' as a metonym for the whole institution. The arrangement is pure Bonn–Berlin compromise: the bulk of the bureaucracy stayed on the Hardthöhe, the public ceremony moved east.

Article 65a of the Grundgesetz makes the Defence Minister the Commander-in-Chief of the Bundeswehr in peacetime; in a declared state of defence, command passes to the Chancellor. Since the 1990s the Hardthöhe has authored a steady widening of what the German military does. The Bundeswehr deployed to the Balkans, flew combat missions in the 1999 Kosovo War, and spent almost twenty years in Afghanistan with the International Security Assistance Force and the Resolute Support Mission before the last German soldiers withdrew on 29 June 2021. The decisions to send them, to fund them, to bring them home — all routed through these unassuming Cold War office blocks. There is no statue out front. There is a checkpoint, and a flag, and a steady stream of staff cars rolling up a hill in Bonn that quietly reshaped what postwar Germany was allowed to be.