> The thing is, if we accept the norms that Qatar can be targeted for kinetic action by Iran for hosting US assets or by the US for hosting Iranian assets, then that opens a MASSIVE can of worms.
None of your examples are actually analogous, they are all more distant support than hosting a base from which direct attacks are carried out except for the first one in which the "can of worms" is justifying attacks on a state that it is already a direct belligerent (and in fact the aggressor) because of third-party support, which, on the other hand, is not analogous for the opposite reason—it is very much not necessary to invoke any third-party action to justify that. The direct belligerence already justifies that.
None of your examples are actually analogous, they are all more distant support than hosting a base from which direct attacks are carried out except for the first one in which the "can of worms" is justifying attacks on a state that it is already a direct belligerent (and in fact the aggressor) because of third-party support, which, on the other hand, is not analogous for the opposite reason—it is very much not necessary to invoke any third-party action to justify that. The direct belligerence already justifies that.