Abstract: A reactive armor includes an orderly stack of multiple leaves of explosive, interleaved with non-explosive compressible foam. The stack is enclosed between armor plates. The armor plates are moveable between a first position in which the stack is compressed and a second position in which the stack is not compressed. An igniter is in electrical communication with the leaves of explosive. Each of the multiple leaves of explosive has a thickness below the “detonation failure thickness” of the explosive. In the compressed state, the compressible foam is compressed and the explosive leaves are sufficiently close to support detonation. In the uncompressed state the compressible foam is expanded and the explosive leaves are not sufficiently close to support detonation, and the use of highly plasticized explosives prevents other types of explosion. The invention provides for switching the reactive armor between an explosive state and a non-explosive state.