If countries have a right to retaliate when they are attacked, you should expect any country to retaliate when attacked

This is another example of how Iran is not treated like other countries. If a "regular country" (meaning a country in the "developed world") had its consulate bombed by another country, everyone would expect the country with the bombed consulate to retaliate. Retaliation in those circumstances is not just expected, it is portrayed as just.

So if Italy bombed the French consulate in Germany to get some mafia figure who was supposedly hiding there, the international community would deem Italy to be a pariah state. And if France vowed to retaliate against Italy, it would be viewed as justice, not as some terrorist threat. That would be true even if the mafia guy really was in the French consulate when it was bombed. Bombing a diplomatic compound is just not how civilized countries deal wit those issues. It would be ridiculous for the U.S. to announce that it would protect Italy against French aggression in that scenario. Italy would be the real aggressor. They attacked French soil!

And yet that is exactly what Biden is doing in this case. Israel bombed an Iranian consulate and killed 13 people. That wasn't in retaliation for anything. They just attacked because they thought bad people were there (although their crime just seems to be achieving a high rank in Iran's elite military unit). Iran's threats to retaliate, something that any other country in its situation would do is viewed as somehow out of bounds.

I get that the Iranian government is awful. But isn't it just easier to focus on the things they do that are awful? When you treat regular behavior as out of bounds, it just discredits any attempt to call them out when they really do stuff that is out of bounds.