And this time, they mean it.

U.S. Secretary of State John Kerry warned his Russian counterpart, Sergey Lavrov, on Saturday that “Russia should not intervene in Ukraine under the guise of humanitarian convoys or any other pretext of ‘peacekeeping,'” according to a senior State Department official.
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Kerry urged “all parties to work through international organizations” to provide humanitarian assistance in eastern Ukraine, the official said.

In a separate call Saturday, U.S. Vice President Joe Biden and Ukrainian President Petro Poroshenko agreed that any Russian action in Ukraine, even for purported “humanitarian” purposes, without the formal, express consent and authorization of the Ukraine government would be “unacceptable and a violation of international law,” according to the White House.

I first caught this story this morning on CNN’s New Day, where Victor Blackwell was conducting an interview with a field reporter on the subject. (Looking for the video on this.) To his credit, Blackwell asked the same question that jumped to my mind immediately. If you draw a line and tell someone not to cross it, but they do, then you draw another line, what motivation do they have to not just cross it again?

Given Vladimir Putin’s recent proclivities, this seems like an invitation to disaster. Issuing orders to Moscow along the lines of, don’t you dare cross the border for your so called humanitarian missions, is just the excuse Putin needs to inform the world that Barack Obama does not run Russian foreign policy. And now that the issue of the need for humanitarian aid to the people afflicted by the conflict has been raised, the temptation is probably even greater. As we talked about yesterday, if Putin was thinking about a direct military incursion into the area around Donetsk, he might have still had the sense to hold back because of the international reaction. But if you can take 20,000 troops and hand them all a care package, the propaganda stage is set for the usual Putin theatrics. Send in the troops while claiming that they are there to “provide humanitarian relief” and then, if an errant shot goes off and they begin firing back, well… it just couldn’t be avoided.

If threats from the United States actually had any weight behind them, Putin would probably be more likely to keep his cards close to the vest and look for a way out of this while saving face. But he seems to have no fear of America at this point, so don’t be shocked if this “relief mission” heads into the Donetsk region, tanks and all.