It took the shooting down of a Malaysian commercial aircraft by pro-Russian rebels to finally break the illusions held by several European leaders about Russian President Vladimir Putin.

Until the tragedy on July 17, leaders from Austria, Italy, Britain, and the Netherlands believed—or rather, deluded themselves—that Putin would bow to the pressure of weak EU sanctions. Germany still held on to the diplomatic option to maintain some dialogue with the Kremlin.

But neither sanctions nor diplomacy have so far been able to deter Putin from turning Ukraine into an ungovernable country and a buffer zone between Russia and the West, with the Kremlin calling the shots.

So on July 29, nearly three weeks after MH17 was shot down, killing all 298 on board, most of whom were Dutch, EU leaders imposed tougher sanctions on Russia. The measures include denying Russian banks access to European capital. If European leaders think that those sanctions will deter Putin from continuing to destabilize eastern Ukraine, they are mistaken.

Moscow continues to arm the pro-Russian rebels, according to a plethora of Western intelligence reports. Russia is still deploying thousands of troops along its border with Ukraine, NATO revealed this week. At the same time, Ukraine’s armed forces rightly seem determined to regain control over towns held by the rebels rather than allow the insurgents to consolidate their grip over Ukrainian territory.

Eastern Ukraine has become so unstable that investigators still do not have unhindered access to the site where MH17 was shot down. So much for Putin’s promise of full cooperation and transparency in dealing with the investigation.

Moreover, as soon as the latest sanctions were announced, Russia imposed a ban on imports of Polish fruit and vegetables, citing health reasons. The Kremlin has resorted to this tactic repeatedly to punish its critics. Moscow has imposed such trade embargoes on Ukraine, Georgia, Moldova, and, indeed, on several Western European countries over the past few years.

This time round, the EU should respond immediately. These embargoes are in breach of WTO rules. The EU should invoke those rules instead of delaying, as it did during all previous import bans. The union should also step in and compensate Poles and those in the EU’s Eastern neighbors affected by Russian embargoes.

Trade restrictions are only one weapon in Moscow’s arsenal. Russia has threatened Europe with higher energy prices, another of the Kremlin’s favored political tools designed to weaken European solidarity and punish Russia’s critics.

That’s all the more reason to complete the liberalization of Europe’s energy market, reach a short-term deal with the United States on importing American energy, complete Europe’s gas and electricity interconnectors, and fill the reserves. Talk of speeding up the process of extracting shale gas known as fracking is illusory. That is a long-term energy strategy, not an overnight solution.

As for the European Commission, it must not buckle by granting exemptions to the consortium involved in Russia’s South Stream gas pipeline project. Gazprom and its European partners are intent on controlling access to the pipeline, which contravenes EU competition rules.

All of the above are soft-power measures. What the EU lacks is the will to use even a minimum of hard power.

At a time when France is selling the most sophisticated hard-power military capabilities to Russia in the form of its Mistral-class assault ship, European countries shy away from using hard power to defend their own interests and values.

As a minimum measure of hard power, NATO should deploy permanent bases in Poland and the Baltic states. This is not about provoking Russia—as if Moscow has not caused enough mayhem in eastern Ukraine. It is about NATO protecting its allies.

The EU and NATO also need to provide far more intelligence and logistics to Ukraine. Of course, Putin could cultivate his conspiracy theories against the West even further by claiming the MH17 plane crash was a ploy by NATO to put boots on the ground in Ukraine.

There is no guarantee that Putin will back down. His popularity is at an all-time high, and Ukraine is too important a price for him to give up now. Yet that is exactly why the West needs to protect its allies and offer as much support as possible to those Eastern neighbors that want to pursue a Western political and economic course. Otherwise, Ukraine and the remains of Europe’s weakened credibility will be lost.