(CNN) -- The killing of 298 innocent people on board Malaysia Airlines Flight 17 was a crime, a consequence of the war against Ukraine that Vladimir Putin started, and which he supplies, directs and controls. The Russian President bears full responsibility for this war, including the downing of the Malaysian airliner. The main problem with our reaction to Russian aggression is not even the mildness of our sanctions, but the lack of clarity of their purpose. Our message to Putin is very confused. Do we want him completely out of Ukraine, or do we want his help in dealing with that country? They are two very different requests.
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Yuri Yarim-Agaev: The West's response to Putin's Ukraine policy has been murky
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He says some are looking to Putin as a potential peacemaker in Ukraine battle
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Author: Putin is the cause of the Ukraine conflict and should be treated that way
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He says the West needs to take a much firmer stance against Russia's actions
To stop aggression against @placeholder and to prevent aggressions against other countries, make Russia pay a high price by introducing sector and other serious economic sanctions.
Take immediate steps to reduce that cost and any dependence on @placeholder.