Despite earlier declarations from opposition leaders in Kiev that the Crimea referendum was illegal and Crimea would always be part of Ukraine, yesterday a plan was announced that Ukraine would pull out all its forces from Crimea. The forces, some 25,000 personnel, will be relocated to parts of Ukraine outside of the Crimea region.

Though not a formal recognition of Russian control over Crimea, it’s pretty close.

While the provisional government in Kiev has insisted that Russia’s annexation of Crimea is illegal and has appealed to international supporters for help, the evacuation announcement by the head of the national security council, Andriy Parubiy, effectively amounted to a surrender of Crimea, at least from a military standpoint.

It came hours after militiamen, backed by Russian forces, seized the headquarters of the Ukrainian Navy in Sevastopol and detained its commander, in what appeared to be the start of a concerted effort to oust the Ukrainian armed forces from outposts throughout the peninsula.

Russian forces, without insignia, have been showing their teeth throughout the region – surrounding bases and in some cases violently clashing with Ukrainian troops. One incident had led to a shooting that left one Ukrainian officer dead. Other Ukrainian forces were effectively imprisoned by surrounding Russian forces. With the new withdrawal plan they will finally be free to leave their installations.

But just because Ukraine may be surrendering to the inevitable does not mean US policymakers plan to. Senator Marco Rubio has penned an op-ed for the Washington Post claiming that by “allowing” Russia to take control of Crimea the entirety of international law and order is threatened.

Vladi­mir Putin’s annexation of Crimea is a direct challenge and long-term threat to the post-World War II international order for which the United States and our allies have made great sacrifices over the past seven decades. If Putin is allowed to take land from a neighboring nation through deceit and raw military force without serious consequences, the precedent could have global repercussions, including in Asia.

Some have suggested that Crimea is not worth triggering tensions with Russia, given other interests that are more important. While it is best to avoid conflict whenever possible, history shows that illegitimate aggressions that go unchallenged are a virtual guarantee of even more dangerous conflict in the future.

Beyond more bluster Rubio also wants the NATO door to stay open for Ukraine which would make any military conflict within the country grounds for a US military response. If Ukraine had been in NATO it would have been hard to justify the US military not responding once Russian forces entered Crimea. In effect, Rubio wants to up the ante with US military forces in a stand off with another nuclear power. But he seems to be in the minority.

As of now it seems everyone is begrudgingly accepting that Crimea is going to stay annexed to Russia.