By launching its long-planned counteroffensive, Ukraine has just taken a decisive step down the path of driving Russian forces from its territory. But it is early days still, and there is much we don’t know.

Confusion is the only thing you can count on during a moment like this. During three tours in Iraq and Afghanistan as a brigade commander and a director of operations, I often had great difficulty visualizing and understanding what was going on in a fight, even with the latest command-and-control systems.

And I certainly was never involved in a fight as large, violent and disorienting as the battles underway in Ukraine. Reports from field commanders to their leaders are typically incomplete and confusing. Drones help, but technology will never fully succeed in lifting the “fog of war.”

Although Western audiences justifiably want to understand how the fight is going in real time, we should remember the axiom that first reports are never as good or as bad as they sound. I think the Ukrainians can and will win this fight. But the summer is likely to be long and difficult. We will not be able to judge how successful the counteroffensive has been for quite some time.

That said, here are some things to keep in mind in these early days.

First, you will know it when you see it.

While the counteroffensive has been launched, I do not think the main attack has yet started. The Ukrainian general staff will want to keep the Russians guessing about where it will take place for as long as possible.

So far, it appears that the Ukrainians are still probing for vulnerabilities they can exploit and reinforcing local tactical successes. As a result, a few villages have been liberated, and about 100 square kilometers of territory have been recaptured. We will know the main attack has started when we see large groupings of armored forces — two or three armored brigades attacking in one direction.

How large is a brigade? Ukrainian tank battalions usually contain 31 tanks, and armored infantry battalions have a similar number of armored vehicles. Each battalion will also contain additional armor carrying engineers, air defense and logistics. An armored brigade would have four or five tank and armored infantry battalions. A typical Ukrainian brigade therefore is likely to have at least 250 armored vehicles of different types.

To date, we have not yet seen these kinds of large armored formations hit the battlefield.

Second, watch the Russian lines.

The Russians have built hundreds of miles of trenches (of varying quality), minefields, antitank ditches and “dragon’s teeth” obstacle belts. These defenses will undoubtedly present challenges to Ukraine’s attack.

But defenses are only as good as the soldiers occupying those trenches and covering those obstacles. I’m waiting to see if the Russians fighting from them are more effective in defense than they were on the attack. The vicious infighting we see between the various Russian military leaders and mercenary bosses highlights the lack of cohesion on the Russian side.

I expect Ukraine to seek to exploit this. A breakthrough along any part of the line could end up being catastrophic for Russian forces as chaos sets in.

Third, don’t over-interpret Ukrainian losses.

Breaking through enemy lines is never easy. Ukraine will suffer setbacks. Images of at least one wrecked Leopard tank and several Bradley Fighting Vehicles got a lot of visibility on Twitter and subsequently in media outlets. Such images are not a reliable indicator of how the fight is going. But they are a reminder that a cakewalk victory is unlikely.

And fourth — perhaps the most vital metric of all — watch how support evolves in Western capitals.

Ukraine is in an existential fight. How long it takes and how many lives it costs greatly depends on what additional support the West offers. Ukraine will need to be resupplied as the war grinds on. The Biden administration announced earlier this week that it will provide an additional $325 million for air defense, artillery, antitank weapons and armored vehicles. This is good.

But longer-range weapons, such as the Storm Shadow missiles that Britain delivered earlier this year, would be even more useful as they would shorten the war. President Biden has been hesitant to send the similar MGM-140 Army Tactical Missile System (ATACMS, pronounced “attack ’ems”) to Ukraine. I hope he reconsiders.

The Biden administration has said it has given Ukraine what it thinks it needs to succeed, suggesting it is up to Ukraine to make maximum use of what it has. This kind of stance can lead to a passive complacency — watching and waiting for battlefield results.

But what Ukraine needs right now are not spectators. It needs ATACMS.