It protects the manufacturer against ramping up supply only for demand to suddenly disappear.
Even that isn't really sufficient. Looking at the capex depreciation table [1], he'll only depreciate the new machinery in five years, and likely still be paying a note on it. Commercial industrial/flex space leases in the DFW area where he's near are typically around 3-5 years. After all is said and done, he's likely roughly breaking even, and not netting a giant personal profit at the other end.
He needs the Federal and state governments committing to evergreen disaster preparedness on a decades-long timescale. That takes much more than stockpiling.
[1] https://cs.thomsonreuters.com/ua/fixa/cs_us_en/ass_life_tbl/...