RIGA, Latvia — As Russian President Vladimir Putin enters his second month of war against Ukraine, questions are mounting about what limitations he could face as he presses ahead with an invasion that has already inflicted great costs on the Russian military and left the country deeply isolated.

Putin for years has snuffed out dissent, muzzled independent media and bolstered a security state to prevent protests, meaning he faces far fewer domestic constraints in waging such a war than the leader of a democratic nation would. Continued revenue from foreign oil and gas sales — despite Western sanctions — also is helping him ease the blow of harsh economic sanctions at home.

But the Russian president does face certain tactical strictures on the battlefield, as well as some geopolitical and economic constraints. They all will probably make his ability to wage a longer-term war in Ukraine more difficult — but far from impossible.

“Time is not on Putin’s side,” said Russian political analyst Tatiana Stanovaya, founder of the Russia-monitoring consultancy R. Politik. She noted that, as the war grinds on and the sanctions set in, the fallout on Russia from the war is likely to compound.

In Warsaw on Saturday, President Biden appeared to sharply widen Washington’s confrontation with Putin, saying the Russian president “cannot remain in power” in a speech that wrapped up a trip focused on talks with NATO allies. Secretary of State Antony Blinken said Sunday that Biden was not calling for “regime change," but was making a point that Putin “cannot be empowered to wage war.”

On the battlefield, Russia has wrested control of a large swath of southern Ukraine at great cost, nearly completing a “land bridge” from Russian territory to Crimea, which Russia forcibly annexed from Ukraine in 2014. But efforts to take Kyiv and Kharkiv, Ukraine’s two largest cities, have stalled. So have attempts to expand Russia’s southern land grab westward to include Mykolaiv and Odessa.

A senior NATO official estimated Wednesday that the Russian military has lost between 7,000 and 15,000 forces in just one month, more personnel than the United States lost in Iraq and Afghanistan combined over 20 years. Thousands more Russian forces have been injured.

New conscripts

Michael Kofman, a Russian military analyst at Virginia-based CNA, said significant Russian casualties do not necessarily seem to be a political limitation on Putin at home but hinder the effectiveness of his units in combat. At some point, Kofman said, high numbers of Russian troops killed or injured affect morale and the ability of commanders to press forward with the campaign.

The Russian military’s draft of new conscripts begins April 1, and Putin will need to issue a decree in the coming days on how many new soldiers Russia’s defense ministry must enlist. He will also have to decide whether to hold on to existing conscripts for longer due to the losses in Ukraine.

The continuation of a multi-front war long term will require significantly more forces and a broader mobilization that so far the Kremlin hasn’t undertaken.

“In April, they are going to have to make a decision about what they are going to do with manpower and the extent to which they are willing to sustain a large war of this scale well beyond what they intended,” Kofman said. “Are they going to commit to a large war or see where they can get in the next couple of weeks?”

The Ukrainian forces’ resistance — and even successful offensives to recapture territory from Russians in some places — could also limit what Putin believes he can achieve and force him to recalibrate his objectives. At the same time, Russian forces are facing difficulties keeping supply lines running on multiple fronts.

But Kofman said Putin’s decision-making depends largely on what information he is seeing and what he is being told. U.S. intelligence regularly assessed in the run-up to the war that the Russian leader was being given poor information by his inner circle of advisers.

“The big question is, what does Putin actually know of this war?” Kofman said. “What is his perception of the reality of the battlefield? What is the military leadership telling him about their prospects for success?”

“The question comes down to: Does he believe continuing to use force can actually achieve any of his political aims in Ukraine?” he added. “Or does he see the situation as one of diminishing returns?”

Nick Reynolds, a research fellow at the London-based Royal United Services Institute, said the Kremlin increasingly will face limitations regarding munitions, manpower and morale, as well as logistics. And those realities may force Putin to change his goal from toppling Ukraine’s government to compelling changes in Ukraine’s political posture, or focusing the war on a single front. Reynolds pointed in particular to the manpower limitations.

“It’s clear that Russia is searching really hard for personnel,” Reynolds said. “It’s not so much manpower — it’s trained and motivated manpower.”

The acceleration of arms deliveries for Ukraine from the United States and Europe will also create more limitations for Putin’s forces on the battlefield. Those include Switchblade drones from the United States that could be particularly damaging for Russian forces in urban combat.

Putin’s energy card

Putin so far has been able to survive the sanctions placed on Russia by continuing to sell oil and gas to customers such as China and India, in addition to Europe, and forcing Russian energy exporters to buy rubles with that revenue, preventing a total collapse of Russia’s currency. With high global energy prices and the ruble’s moderate devaluation, Putin probably will have cash on hand to cover Russian government costs and spend on economic stimulus.

Still, the economic head winds are likely to compound for Russia as gross domestic product contracts and unemployment rises, and new escalations on the battlefield could lead to new sanctions.

In the meantime, Moscow will find itself increasingly reliant for goods and technology on China, Turkey, Israel and other nations that haven’t sanctioned Russia over the invasion. Putin’s ability to keep those countries on side, especially China, as the war continues and possibly escalates will affect what Russians can buy, access and produce.

Alexander Gabuev, a senior fellow at the Carnegie Moscow Center who specializes in Russia-China relations, expects Beijing will not want to be seen as enabling Putin’s war machine or jeopardize Western business, so probably will not violate sanctions or supply a pipeline of arms.

“Otherwise, a wild game of opportunities is there — cheap commodities purchases and getting ahold of the most advanced military technology,” Gabuev said. “China will be clever in continuing to pursue this.”

For weeks, American and European officials have been looking to see whether the war is causing rifts within the Russian elite, particularly the intelligence and military circle around Putin, a possible limitation for the former KGB officer as he continues the war.

Despite reports of recriminations within the Russian security establishment, and questions about the public absence of Defense Minister Sergei Shoigu and Chief of the General Staff Valery Gerasimov, no obvious rifts have been confirmed publicly. The only top Russian official to leave the country over the war so far is Anatoly Chubais, Putin’s sustainable development envoy.

Stanovaya, the Russian political analyst, dismissed the notion that the country’s hard-line security elite, often called the siloviki, would rise up against Putin, particularly under the current circumstances in which they have vast power.

“Today, it is impossible to imagine anything like this,” she said. “There is no discontent among the security services. This is all fairy tales.”

The broad sanctions against the Russian elite reduce the chance of any public break with Putin, Stanovaya said, because sanctioned members of the elite have nowhere obvious to go — such as havens in Europe — if they decide they disagree.

For years, Putin offered Russians stability and economic growth, even as they exchanged their political freedoms for a more authoritarian system. The economic contraction due to sanctions probably will make it impossible to present consumer well-being and living standards as an achievement.

“Now, Putin will have to offer the Russian people something else. He has no economy anymore,” said Kirill Martynov, political editor of the Russian independent newspaper Novaya Gazeta. “And it looks like the thing that he can feed Russians is a kind of political greatness: Look, we just are back in the club of great countries. Every European leader wants to talk with me because I’m so great and so dangerous.”

Martynov said the appeal of that messaging will diminish if economic conditions become particularly dire — though the government probably will continue to focus on geopolitical events as a distraction.

“I mean, if you cannot do anything with your economy, and you can’t do anything with your society, the only thing you can do is to be quite dangerous,” Martynov said. “Putin can start any war he wants.”