Russian forces have Ukraine surrounded, stirring invasion fears. Here's what each side could bring to a war

• Russian forces have surrounded Ukraine, causing concern that Russia may invade its neighbor.
• While war on Ukraine's turf may give it a slight advantage, Russia's military is much larger and more powerful.
• However, an invasion could spell economic trouble for Russia in the long run. 

Russia has surrounded Ukraine militarily, with more than 100,000 troops amassed at various positions along the border, and there are fears that Russia may decide to attack.

Russia has denied plans to invade, but a number of Western nations are skeptical, especially as Russia continues to maintain an alarming force posture near its neighbor.

—ISW (@TheStudyofWar) January 26, 2022

White House press secretary Jen Psaki warned last week that Russia could "at any point launch an attack on Ukraine" and described conditions at the border as "an extremely dangerous situation," and Pentagon press secretary John Kirby said on Thursday that a Russian incursion into Ukraine "could be imminent."

But Russia continues to argue it does not want conflict. "If it depends on Russia, then there will be no war," Russian foreign minister, Sergey Lavrov, told Russian media Friday. "We don't want wars. But we also won't allow our interests to be rudely trampled, to be ignored." The Pentagon has said Russia's intentions "remain opaque."

Amid the continued uncertainty of whether or not Russia will launch a military offensive against Ukraine, Insider spoke with an expert about what each side could bring to a fight. 

Ukraine's Strengths

Any war fought on a nation's home turf gives them a slight advantage, according to Jeffrey Edmonds, a former US Army tanker and CIA military analyst, and Ukraine is no different. 

"They just understand their own terrain more, their logistics are behind them as well," Edmonds, now a Russia expert at CNA, said of the Ukrainian military. "It's easier to defend one's own terrain than it is to invade someone else's."

Edmonds stressed that this is not a major advantage though. Ukraine is still largely at the mercy of Russia's superior military. 

That said, the former Soviet territory's military has grown and modernized since Russia's unimpeded annexation of Crimea in 2014 and could inflict substantial harm on Russian forces.

Eight years ago, Ukraine had around 6,000 combat-ready troops, but today they have 145,000-150,000, according to a recent Congressional Research Service report.

Ukraine's Weaknesses

Despite improvements in capacity and capability, Ukraine's biggest weakness in the face of possible Russian aggression is its lack of military power. Its $5.9 billion military budget is no match for Russia, which spent $61.7 billion on its military in 2020 alone.

Since 2014, the US has given Ukraine $2.75 billion in military aid and has helped the country modernize and reform its defense sector, The Washington Post reported. And, as a potential conflict looms, the US and NATO have been providing additional support, including lethal aid.

The US and other NATO members have sent Ukraine weapons – such as anti-tank Javelins and counter-air Stinger missiles, but the aid is limited and unlikely to change the course of the battle, Edmonds said. "I think Russia has more than enough to deal with that," he said.

"It's not as if NATO is fighting the Russians," Edmonds said. "We're giving the Ukrainians enough to try to punish the Russians to a degree, but I don't know that it's decisive."

Russia's Strengths 

Russia's greatest strength is its large and technologically-advanced military that outmatches Ukraine on every level. Russian forces, which have also modernized and improved over the years, have more power on land and in the air.

Russia has around 12,000 tanks, 30,000 armored vehicles, and 12,000 self-propelled artillery, USA Today reported. In comparison, Ukraine has 2,500 tanks, 12,000 armored vehicles, and a little more than 1,000 self-propelled artillery. And Russia has 700 fighter aircraft, while Ukraine only has 70.

Russia also dominates at sea, with 15 destroyers, 70 submarines, 11 frigates, and nearly 50 mine-warfare vessels. Meanwhile, Ukraine has no destroyers or submarines and only one frigate and one mine-warfare vessel.

Edmonds highlighted Russia's air force, as well as its long-range strike platforms, noting that these could have an outsized impact in a conflict.

"Ukraine just doesn't have much of an air force, especially opposite of the Russian air force," Edmonds said. "I think it can be pretty decisive in the opening days of conflict."

Edmonds suspects Russia's strategy will be to surround Kyiv, trying to force a political change in the country through physical force. 

"This isn't going to be just turning up the heat in the east or hybrid warfare," he said, "This is going to be regular tank-on-tank, aircraft-on-aircraft warfare."

Russia's Weaknesses

Most of Russia's weaknesses exist not on the battlefield but in the country's long-term economic prosperity, Edmonds said. 

"The West is likely to punish Russia," he continued. "They have a bunch of reserves saved up in case you sanction them, but they're as vulnerable as everybody else is to sanctions."

But the bigger issue for Russia, were they to invade, would likely be reactions from international investors. For example, Edmonds said, it is difficult for companies like ExxonMobil to justify expanding their operations to a country seen as unpredictable because it invaded another country. 

"No one's going to want to invest in Russia after this," he said. "It's an optics problem there."

Another factor not on Russia's side is time. The longer Russia keeps its military waiting around, the worse off they will be, Edmonds added. 

"The Russians need to pull the trigger sooner rather than later because it is costly for them to sit on the border," he said. "Readiness goes down because you're not at your ranges. Morale goes down because you're not doing anything."

But because these weaknesses do not tremendously affect its ability to wage war against Ukraine, Russia would almost certainly win against its neighbor, Edmonds said, adding that he just doesn't "see the Ukrainian military standing much of a chance."