US President Joe Biden put it bluntly on Tuesday when he said in a speech that the United States and its allies will “not tire” of backing Ukraine — a message seemingly directed at his Russian counterpart Vladimir Putin.

Since Russia launched its assault a year ago, the US has provided billions of dollars in aid to Ukraine, which experts say is necessary not only to back Ukrainians but to advance US national interests.

Despite opposition from some US politicians, Washington should be able to maintain this level of support to Kyiv in the long term, analysts argue.

“This policy is definitely sustainable,” said Simon Miles, an assistant professor at Duke University’s Sanford School of Public Policy.

Miles told Al Jazeera that, while the assistance seems significant in terms of the dollar amount when put in the context of the entire US government budget, the numbers are “not overly large pieces of the whole pie”.

“The amounts of money we’re talking about are, I think, a pretty small price to pay if you look at what the alternative is — what it would mean for Vladimir Putin to succeed, for not just the United States and its place in the world but in fact for the entire global commons.”

‘Appeasement doesn’t work’

Washington marked the first anniversary of the invasion on Friday by announcing new aid to Ukraine and sanctions against Russia — the two main tools it has used to back Kyiv.

“The United States will continue to work with its allies and partners to provide Ukraine with capabilities to meet its immediate battlefield needs and longer-term security assistance requirements for as long as it takes,” the Pentagon said on Friday.

The US Congress approved more than $100bn for Ukraine through four spending bills last year — funds that the Biden administration has been dispensing through periodic military, humanitarian and budgetary aid to Kyiv.

According to the Treasury Department, the US government spent $6.27 trillion overall in the 2022 fiscal year.

“We have learned repeatedly in the 20th century that appeasement or hiding from reality doesn’t work. It only encourages the aggressor,” said Igor Lukes, a professor of international affairs at Boston University’s Frederick S Pardee School of Global Studies.

Lukes added that, if Putin were to conquer Ukraine and get to its western borders, Russia would be “eyeball to eyeball” with several NATO countries, including Poland and Romania.

The US-led alliance has a collective defence pact, meaning an attack on one country is considered an attack on all.

“Opposing Putin now and opposing him in Ukraine is an American national interest,” Lukes told Al Jazeera.

He said the war in Ukraine is “clear-cut” foreign aggression by one sovereign nation against another, making it a global matter. “The war is not about Ukraine only. It’s also about us,” he explained.

US Secretary of State Antony Blinken echoed that assessment at the United Nations Security Council on Friday.

“Nations around the world continue to stand with Ukraine because we all recognise that, if we abandon Ukraine, we abandon the UN Charter itself and the principles and rules that make all countries safer and more secure,” Blinken said.

Far-right dissent

Still, a small but vocal contingency of far-right legislators in the US Congress has been increasingly critical of Washington’s aid to Ukraine.

Ultraconservative legislators slammed Biden earlier this week for visiting Ukraine, accusing him of ignoring crises at home in favour of a foreign conflict.

Lukes said such voices are “waiting for an opportunity to make a spectacle of themselves” and remain on the fringe, stressing that Ukraine has been a unifying issue in a deeply divided Washington.

I think Senator Romney would be the first to tell you that we don’t always agree.

But he knows what I know: that standing with Ukraine — and standing up for freedom — advances our national security. https://t.co/X67SkDIL6W

— President Biden (@POTUS) February 24, 2023

Matthew Pauly, an associate professor of history at Michigan State University, said no one can advance a “reasonable argument” that a Russian victory in Ukraine would not threaten US interests.

Russia launched its all-out invasion of Ukraine on February 24, 2022 — one year ago — after a months-long standoff that saw Moscow amass troops near the Ukrainian borders as Putin demanded an end to NATO expansion into former Soviet republics.

But Washington stresses the invasion is not about NATO or Russian security interests but is rather a push by Putin to erase Ukraine’s national identity.

“This is a war that is imposed on a sovereign nation by another nation. And if the Ukrainians are willing to fight for the security and peace of Europe, the least the US can do is support them in this effort because it’s in the direct strategic interests of the United States,” Pauly said.

He described the Russian invasion of Ukraine as a “discernible” threat to the US.

“The defence budget — some can argue about the nature of that but why does it exist if not to protect the United States? So in my view, this is where expenditures are absolutely justified because the security threat is real,” Pauly told Al Jazeera.

‘Just and durable’ peace

Pauly stressed that Ukrainians desperately want peace.

On Friday, Blinken called on the international community to pursue a “just and durable” peace in Ukraine.

“History teaches us that it’s the nature of peace that matters,” Blinken said.

“For peace to be just, it must uphold the principles at the heart of the UN Charter: sovereignty, territorial integrity, independence. For peace to be durable, it must ensure that Russia can’t simply rest, rearm and relaunch the war in a few months or a few years.”

Pauly said a just peace would entail “the liberation of all Ukrainian territory”, including Crimea, which Russia illegally annexed in 2014.

For his part, Miles, the public policy professor at Duke University, said it will be up to the Ukrainian government to decide where to draw the line.

“The mood in Kyiv today really does not seem to be that they’re interested in ceding any ground,” he added. “They’re going to prosecute this to the finish, in large part because they don’t want a sort of frozen conflict or a simmering grey zone conflict going on on their borders.”

But Putin has signalled that Russia will not relent and will pursue the conflict for the long run.

Miles said that, though the Russian army has been “greatly degraded” after “taking a beating” over the past year, Putin will still have a major say in when the war ends.

Some dovish foreign policy advocates and European leaders have warned against pushing Putin too hard, noting that — despite its setbacks in Ukraine — Russia remains a nuclear power.

Russian officials have hinted at the risk of a nuclear war over the past year but Washington says there has been no detected change in Moscow’s nuclear posture.

Pauly said that, while threats should be taken seriously, Russia’s intent is to “weaken [the] unified resolve” of the US and its allies.

Miles also played down Moscow’s nuclear threats or risks of direct confrontation between the US and Russia.

“What message does it send to other nuclear powers, other would-be nuclear powers, if they believe that you can get away with anything by just rattling the nuclear sabre?” Miles said.

“I think a world in which there are no consequences for states with nuclear weapons for grotesque misbehaviour, like Vladimir Putin right now, is a more dangerous world.”