When I was in graduate school in the 1990s—and this continued into the aughts and 2010s—the dominant idea in liberal foreign policy circles was that of “humanitarian intervention.” The claim was that though states should ordinarily respect the sovereignty of other states, under extreme circumstances, say of genocide or ethnic cleansing, it was not just the right, but the obligation, of the international community, to take coercive action, including using military force and violence, to stop the genocide or ethnic cleansing.

Occasionally, the theory went, this might involve or entail toppling the regime that was engaged in the genocide. Thus Vietnam was allowed to invade Cambodia and overthrow the Khmer Rouge, Tanzania was allowed to invade Uganda and topple the Idi Amin regime, NATO overthrew Milosevic, France invaded Rwanda to establish a safe zone there for the Tutsi, and so on.

While these actions were often framed as the obligation of “international community,” the fact that the actors were usually neighboring states or former colonial overseers suggests that power politics was accepted as a legitimate adjunct to the humanitarian intervention regime. That local or former colonial states might have other interests besides humanitarian ones—that the interveners were not always the United Nations as a whole—did not detract from the fact that military violence was being used to stop genocide.

Again, this was a common liberal mainstream opinion between the early 1990s up through the Obama administration, which saw NATO intervene in Libya on similar grounds.

Now we’re confronted with a genocide in Gaza. Should neighboring states be authorized to invade Israel and stop the genocide there, even if that means the Netanyahu regime is toppled? (And don’t forget: the Vietnamese who overthrew the Khmer Rouge were hardly models of liberalism or democracy themselves.) What say the liberal humanitarians now? Where have all the liberal humanitarians gone?