We've done the experiment indeed; see the historical example of the Spanish conquistadors. Other than that I'm not aware of it, so we don't know if such an atta

We've done the experiment indeed; see the historical example of the Spanish conquistadors. Other than that I'm not aware of it, so we don't know if such an attack could work. Its a hypothesis. The original SARS and MERS were too deadly to spread widely. In order for the attack to work, you don't need a disease which is lethal. All you need is a disease which makes your enemy ill enough to attack their infra, while you're immune (e.g. via full vaccination, or because of group immunity from antibodies). Right now, Israel is practically immune to COVID (and was the quickest to get vaccinated), while their surrounding regions are not. This could give them an advantage in warfare, should they decide to initiate such (legit or via proxy). Which, incidentally, is also why is was clever of Israel to pay large sums of money for the vaccines.