Acts of War, declared or not, are excluded in virtually all policies @Generalee (as is terrorism.) The other issue is that were they not excluded perils there's a pretty-decent risk that the insurance company couldn't pay, and insolvency ruins your claim anyway.

Most of the time (e.g. in Florida) the regulators catch this due to required reserve ratios and monitoring before it goes to shit on policyholders, BUT NOT ALWAYS. In the event of an actual Act of War the risks are much higher because the damage is likely to be widespread enough to bankrupt virtually ANY insurer.

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