It arose in the context of maritime shipping, and so was essentially an analogue to floodplain exclusions — i.e., “If you’re going to sail in defiance of a likely sinking or seizure by a hostile power, don’t expect us to make you whole.” It later was included by convention in property and casualty contracts as well.
In the US, at least, Zurich’s attempt to wriggle out of payments would be an uphill battle at best — there are unfavorable judgments in the context of international terror attacks, as well as (in Multi-Foods vs United Commercial) Russian seizure of goods. In the absence of actual war or war-like activities (such as Korea or Vietnam), hard to see how they win. But, hey, even a 5% chance of victory is probably worth the cost of litigation.
In the US, at least, Zurich’s attempt to wriggle out of payments would be an uphill battle at best — there are unfavorable judgments in the context of international terror attacks, as well as (in Multi-Foods vs United Commercial) Russian seizure of goods. In the absence of actual war or war-like activities (such as Korea or Vietnam), hard to see how they win. But, hey, even a 5% chance of victory is probably worth the cost of litigation.