I'm morally sympathetic to President Trump's sale of M107A1 sniper rifles to Ukraine. That rifle will afford Ukrainian ground forces a potent means of attacking light-medium armored vehicles utilized by Russian-supported rebels.

But while I recognize the tactical opportunities here, I'm concerned how this might affect broader Russian strategy. Because Russian President Vladimir Putin is likely to escalate in response to this decision.

Now don't get me wrong, Putin's escalation can be countered by reciprocal U.S. escalation. If, for example, Putin was to authorize a new ground offensive in response to this arms sale, the U.S. could and should respond by providing Ukraine with a plentiful stock of Javelin anti-tank and stinger anti-air missile systems. The U.S. should also push the Europeans, specifically the British, to engage in new sanctions against Russian investment interests.

The problem is what happens if Putin escalates and the U.S. doesn't respond. Absent that resolve, the Russian leader will seize the initiative and consolidate his grip over Eastern Ukraine. And be under no illusions, Putin isn't playing games in Ukraine.

As I explained in January, it seems clear that "Putin intends to carve out an area of southeastern Ukraine to include the city of Mariupol. Taking Mariupol would give Putin control of contiguous territory right down to the Sea of Azov. But Mariupol is also the endpoint of Ukraine’s North-South H-20 highway and a junction of southern Ukraine’s East-West E-58 highway." This makes the city a strategic node with which to anchor long term Russian control in Ukraine.

From special forces to arms supplies to assassinations the Russian government continues to operate an aggressive, multilayered action in Ukraine. But with a major Russian military command sitting just east of the Ukrainian border, a conventional Russian invasion cannot be ruled out.

Consequentially, Trump must do all he can to deter Russia alongside this arms delivery.

Unfortunately, at present, he's doing the opposite. As Josh Rogin notes, the White House is keen to play down this announcement in the fear that playing it up will attract Russian ire.

It's the wrong way to deal with Putin. After all, when dealing with the KGB maestro, once you've made a decision, you have to commit to the course and commit to changing course only where your assessment of interests changes. If Putin senses you're giving an inch, he'll take a mile or he'll bury you under ten meters of rubble.

Don't believe me? Consider former President Barack Obama's credibility; which now lies amid the wreckage of MH-17 and the ruins of Aleppo.

Similarly, while Trump deserves credit for taking this decision, it remains a problem that he is desperate to earn his Russian opposite's favor. In the context, for example, of escalating threats that Russia might bomb U.S. forces in Syria, this moment requires Trump to ensure that Putin knows he won't back down to intimidation.