While the concept lost some of its relevance at the end of the Cold War, it is back in the spotlight with the return of ...

American Canyon supports adding to its sphere of influence 157 acres near both wetlands and industrial land, with the owners contending the soils of the former vineyards are now too salty to farm.

A sphere of influence refers to a geographical area that a power has unilaterally declared to be its exclusive space and over which it exercises political, economic and military control.