During Struck's tenure, Germany was trying to revamp its military into a nimbler fighting force capable of responding to smaller, regional conflicts.

[7][8] During his time at the Defence Ministry, Struck oversaw the early years of Germany's engagement in Afghanistan, famously coining the phrase that "German security is being defended in the Hindu Kush".

[9] In 2004, he said “there will be a clear no from the German side” to any request to place the NATO-led International Security Assistance Force and Operation Enduring Freedom under a unified command, expressing fears a unified command could be a step towards merging the two forces and that political opposition and military dangers could increase if their soldiers were identified with the US-led coalition.

[11] In 2003, Struck dismissed General Reinhard Günzel, the commander of a German special forces army unit, after he praised Martin Hohmann, a conservative member of Parliament, for a speech that had been widely criticized as anti-Semitic; Struck called Günzel a "lone, confused general who agreed with an even more confused statement.

Struck suffered from poor health in the last several years of his career and died of a heart attack in the Charité hospital in Berlin on 19 December 2012.

In a Parliament debate some days later, Jürgen Gehb, CDU Speaker for law politics, said that "we will try to continue working with you, but with minimal contact to your backside".