Suppose the US government is right, and it is totally OK to indiscriminately kill a bunch of bystanders and innocents to get to a single target who allegedly is

Suppose the US government is right, and it is totally OK to indiscriminately kill a bunch of bystanders and innocents to get to a single target who allegedly is an enemy. Isn't it OK then to selectively, cleanly, kill one alleged enemy with Polonium tea? Why these two cases get so different coverage?