Final answer:
Wehler's term for Germany's use of foreign policy to support domestic issues is Social Imperialism, which is exemplified by the pursuit of Lebensraum and appeasement strategies in the lead-up to World War II.
Step-by-step explanation:
The term used by historian Hans-Ulrich Wehler to describe Germany's utilization of foreign policy to address internal issues is Social Imperialism. This concept explains how a nation may use external expansion and conflicts to unify its population and direct attention away from domestic issues. Historical examples include the ambitions for Lebensraum, or living space, by absorbing regions with German-speaking populations, and appeasement policies during the prelude to World War II, where Germany's foreign actions were directly linked to its national interests and domestic strategies.