Six months after Russia invaded Ukraine, the war has apparently settled into a stalemate. The front line has hardly moved in two months.

Casualties on both sides have been immense. In a fashion almost reminiscent of the First World War, recent advances in military technology have greatly strengthened the power of the defensive, while weakening the massed armored forces backed by airpower that in the generations after 1939 were responsible for “Blitzkrieg” style offensive victories. Hand-held anti-tank and anti-aircraft missiles, together with mobile artillery and drones, are now masters of the battlefield, and cause frightful losses to tanks, armored personnel carriers, ground attack aircraft and helicopters.

Nor does it seem likely that this picture is likely to change much in the foreseeable future. The factors that have worked against Russia will do the same to Ukrainian forces if they launch mass offensives. At most, Ukraine might recapture Kherson, by cutting Russian lines of supply over the Dnieper river. Russia might take the whole of the Donetsk region, thereby achieving one of the key stated goals of the original invasion; but it seems extremely unlikely that either side can gain a complete victory.

The biggest risk to Ukraine is probably that they launch an offensive that fails badly with losses so heavy that this allows Russia to launch a successful counter-offensive. Even in this case however, the gains are likely to only be limited.

It is important to remember how very unexpected this is. Before the war, both Russia and the West expected a quick Russian victory. Western diplomats fled from Kiev. Analysts predicted a Russian occupation of the whole of Ukraine, and a Ukrainian government in exile.

What we therefore need to recognize is that Ukraine — with massive military help from the West — has already won a great victory, though not a complete one. As a result, Ukraine has achieved its most vital goal, that of securing its independence and its chance to move towards membership of the West. This success has been achieved on the battlefield, but perhaps even more importantly through the demonstration of the strength and unity of Ukrainian nationalism.

This is therefore arguably no longer an “existential” struggle for Ukraine. It is a battle for limited amounts of territory in the east. By the same token, Russia has suffered a massive historic defeat. Moscow’s hope of turning the whole of Ukraine into a client state has been destroyed for all foreseeable time. This reverses almost 400 years of Russian and Soviet history, from the 17th Century to 1991, as well as rendering empty in contemporary terms the fact that from the 9th to the 13th centuries the areas that are now Ukraine and Russia were part of one country, Kievan Rus.

The idea that Russia can successfully install a puppet regime in Kiev backed by the Russian army is now as fantastical as the notion that it could do so in Warsaw or Prague.

A second conclusion is that Russian military prestige, and therefore the idea that Russia has the capacity to invade NATO countries, have been badly damaged. This thought may seem counter-intuitive, but in some ways, since the Russian invasion of Ukraine, the West is in a stronger position vis-a-vis Russia, and can now afford to be less afraid of Moscow, not more. The idea of Russian tank armies sweeping across Poland into Germany is obviously chimerical.

The risk of unintended escalation to nuclear war does however remain very real. Since nuclear weapons are the one area in which Russia remains a superpower, there is an obvious temptation for Moscow to engage in nuclear brinkmanship — and anyone who decides to walk along a brink runs the risk of falling over it.

Whatever happens, Ukraine will not join NATO — because the alliance has made it abundantly clear that it will never fight for Ukraine. On the other hand, Russia’s invasion and ensuing atrocities have ensured that Ukrainians will never again consider themselves naturally linked to Russia. 

Moreover, due to the tremendous Western sympathy generated by the war, Ukraine does now have the chance to achieve something much more important than NATO in terms of real westernization — membership of the EU. However, Ukraine cannot even start on the long path of reforms needed to achieve this goal as long as the war continues and dominates the Ukrainian economy and society. This is a strong argument for Ukraine to seek an early compromise peace.

From a U.S. point of view, keeping the war going indefinitely in order to weaken Russia has also been proved unnecessary. Russia has shown that it is already too weak to threaten really vital American interests, except through nuclear escalation and economic damage — both of which threats will be increased, not lessened by an indefinite prolongation of the war. We should also remember that on one key issue, that of Islamist terrorism and the threat from the Islamic State and other extremist groups, U.S. and Russian interests are still aligned.

The real threat to American and Western interests if the war in Ukraine continues is the collateral damage to their economies and that of the world from the war, Western sanctions, and Russian retaliation. The struggle against climate change has already suffered severe damage as a result of the flight back to energy security in the form of coal and an expansion of fracking for oil and gas. The danger from climate change has been drastically emphasized by the heatwaves that have swept India, Europe and China in recent months, and their effects on agricultural yields. When it comes to assessing the most dangerous threats to the citizens of Western countries, climate change should take precedence over Russia.

Starvation, political unrest, and increased migration threaten in key parts of the world as a result of these heatwaves on top of the cuts in Russian and Ukrainian grain and fertilizer exports. And in the West itself, inflation, energy shortages and economic hardship risk fueling still further domestic political extremism and instability. 

These are the greatest threats of this war to the West, and the strongest arguments for seeking an early political solution. Of course, Ukraine’s agreement to any settlement is essential; but the United States and the West have given massive support to Ukraine, on a scale that dwarfs their assistance to any other part of the world. They and their citizens are suffering considerable economic damage as a result of the war, and risk much greater damage to themselves and the world in future.

This gives the West, and the United States in particular, both the right and the duty to have a say in the search for an agreement to end the war. And like any viable settlement, this must be based on a recognition of basic realities: that even if an agreement may entail some limited territorial revisions, Ukraine’s independence and path towards the West are now fixed and unchangeable.

The time to begin negotiations for peace is now, not after months or years in which tens of thousands more people have died and Ukraine has suffered still greater harm.