One the dumber responses to criticism of Trump’s recognition of the Israeli claim to the Golan Heights has been to claim that it isn’t illegal to annex territory captured in a “defensive” war. Israeli legal experts reject that shoddy reasoning:

Prof. Aeyal Gross, of the Tel Aviv University Faculty of Law, who writes in Haaretz, agrees that Trump’s declaration has no real legal implication. “President Trump, who is known for his disregard for international law, can’t change it with one declaration and international law is very clear that territory conquered in war must not be annexed unilaterally – it doesn’t matter at all whether you were the aggressor or the defender.”

It shouldn’t be hard to understand that all acts of annexation are illegal under modern international law. The circumstances surrounding how a state took possession of that territory can’t change that, and we can see why it would undermine international law if there were an exception made for wars of “self-defense.” For one thing, virtually every state claims that it is acting in self-defense when it goes to war. There are not many governments that would admit to launching a war of unprovoked aggression. The 1967 war is an unusually poor example of a war of “self-defense” in any case, but that is beside the point. If all that is required to legitimize an illegal act is to declare that the theft of land was done while engaged in “self-defense,” any state that wants to settle a territorial dispute with its neighbor will simply present itself as the victim and try to seize the disputed land by force.

The Israeli government’s position is that they stole the land fair and square, but such land grabs are never permissible under international law. If we start to make exceptions to that rule, the rule will very quickly fall apart and many states will conclude that they can get away with seizing territory from their neighbors. Trump’s decision to recognize the Israeli claim to illegally annexed land is an affront to international law and makes a mockery of our government’s pretense to respecting the “rules-based order.”