If Russia invades, what can Ukraine do?

If it happens, Russia gets to choose when and how. Only then do Ukraine’s far more limited choices come into play.

Ukraine will react based on the scale of a Russian invasion and the directions from which it comes. The bigger the invasion, the more difficult choices there are.

Let’s take the mid-range scenario in which Russian forces look as if they’re driving westwards all the way to the Ukrainian capital whilst simultaneously coming up north from Crimea to join the peninsula with the parts of the Donbass region it already occupies. A cyber-attack on Ukraine’s command and control systems would very quickly be followed by massive air and missile strikes against the air force, air defence systems, and, if intelligence has found them, the stores of anti-tank missiles recently sent to the country by the UK and US. Troop concentrations would also be targeted.

Through this chaos Ukraine must then decide if it sends up its remaining fixed wing aircraft. Given how few fighter jets it has, their condition, and lack of pilots with combat experience, ordering them to fly would be close to ordering suicide missions as the Serbs learned in the early stages of the 1999 Kosovo War. Complete Russian air dominance is almost certain.

Kiev must now order some of its troops to emerge from their shelters. Calls will already have gone in to friendly NATO countries asking for satellite intelligence in spotting where the advance is coming from, but the Ukrainian military also needs its reconnaissance units out and about.

In our scenario Russian ground forces, infantry and mechanised, are now moving, probably from several directions. In the Donbass region the front lines are already close and so fighting there will break out immediately. At this point accurate intelligence is vital. Russian troops may well be coming up from Crimea and down from Belarus. But what if this is a feint? Do they divert substantial forces to the south thus weakening the eastern front?

Within hours Kiev will also have an idea of whether Moscow intends to take the major cities in the east or bypass them hoping they will surrender later. Given the difficulties of urban warfare the likelihood is the Russians will go past and leave them to be encircled by follow-up troops. An exception could be made for Kharkov which is very close to the border and houses important road and rail junctions and would be useful as a supply base.

It’s between 150 and 200 miles to Kiev from the current positions of the Russian troops to the north and east. Some military experts argue they could be in the capital within hours, most say it would take several days at least. The Ukrainians will have hoped to blunt and slow the advances. All the 255,000 active service personnel will have been on full alert and the call up of some of the 900,000 reservists will be stepped up.

The military is far better equipped and trained than it was in 2014. The US has sent sniper rifles, night vision equipment, grenade launchers, radar, and Javelin anti-tank missiles. However, Ukraine’s heavy armour, especially its tanks, are outdated, and it lacks long range ‘stand-off’ missiles. Despite significant advances in skills as a fighting force it is probably still a decade away from being NATO standard.

Kiev will be hoping to inflict significant losses on Russian forces and slow them down, but grinding them to a halt seems unlikely in the first few days. So now they now must decide if the bulk of their forces fall back towards Kiev, and if they should blow the bridges and rail tracks behind them. The attacking force has brought bridge laying equipment with it so if Putin’s army still looks as if it can break through to the Dnieper River in front of Kiev another decision has to be made. Is the order made to open the dams along it and flood some of the ground? Finally, at a certain point Kiev could sue for peace or hold what it can and turn to guerrilla warfare.

There are many scenarios including the whole build up being a bluff. Others include just a few thousand infantry crossing into already occupied territory as “peacekeepers”, to taking half of the country and cutting the rump off Ukraine from the Sea of Azov to the Black Sea. In all cases Kiev has another choice. To save the country does it surrender or fight? If it happens, all indications are that it will fight.