(DER SPIEGEL) — The B61 is the last remnant of the Cold War in Germany. An estimated 10 to 20 of the atomic bombs are thought to remain in storage at a German Air Force base in Büchel, a village in the Eifel mountains of western Germany. Should war break out, the Tornado aircraft belonging to the German Air Force could immediately be armed with the weapons for sorties under US control.

But the fact that such a scenario is considered extremely unlikely has not prevented the US from embarking on an effort to upgrade the stockpile, as it is doing with much of its nuclear arsenal. The Life Extension Program (LEP) for the B61 — of which there are between 160 and 200 in Europe — is considered to be the most difficult and expensive of all. In 2010, the Department of Energy requested almost $2 billion (€1.6 billion) for the project, to be spent over four years. Later, the number rose to $4 billion.

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