Crossing the Ukraine border makes little sense for Vladimir Putin's troops

With the war of words over the deaths in Ukraine’s port city of Odessa still raging, the focus of the conflict moved back to the town of Slovyansk, deep in eastern Ukraine. Here, an uneasy stand-off came to an abrupt end when pro-Russian fighters brought down a helicopter with machine-gun fire.

Still, the impression remains of two governments – one in Kiev, the other in Moscow – mercifully reluctant to escalate hostilities, even as the pro-Russian forces in eastern Ukraine do their utmost to increase and consolidate their gains.

The slow and tentative nature of Kiev’s efforts to restore central control in the east reflects the forceful opposition of local people and doubts, too, about the reliability of the troops, if ordered to fire on fellow Ukrainians. Harder to read is why Russia, which lost no time in seizing, then annexing, Crimea, has not so far intervened – overtly at least – to support those Russian-speakers who are resisting Kiev in the east. After all, Moscow has upwards of 40,000 troops close to the border and, if President Putin’s ambition is to restore something like Soviet-era borders, this is where he would move next.

Western governments might like to believe that it is the threat of more sanctions that is holding Russia back. There are more likely explanations. The most obvious is the enormous risk and enduring cost of such an operation. Russian forces would not be guaranteed a welcome if they crossed the border – easterners might well rediscover their inner Ukrainian – and even mighty Russia could be sucked into a conflict it could not control.

More subtly, it is argued that Russia can achieve its immediate objectives by keeping its military presence at the border, injecting special forces to mount provocations and stir things up, and standing ready to supply more and heavier arms to anti-Kiev militias if need be. Russia may well hope that this will be enough to ensure the east of Ukraine remains within its orbit and constrain any government that might want to take all Ukraine into the Western camp.

Assurances given by Putin and his Foreign Minister, Sergei Lavrov, to Western leaders suggest that Moscow wants to avoid an invasion at all costs. It is worth noting that the Kremlin has resisted calls for direct help from local officials in eastern Ukraine. To date, any evidence even of indirect Russian intervention remains unproven.

If, however, eastern Ukraine remains out of control, as Kiev admits, and fighting spreads, any bets on Russian restraint must be off. Seen from Moscow, the motive would be to prevent a breakdown of security on Russia’s borders. This is not an interpretation that would find favour in the West.