(The Hill) — The Biden administration is under pressure to stream more offensive and defensive rocket systems into Ukraine as the former Soviet country faces a critical tipping point on the battlefield with Russia. 

As Ukrainian forces battle with Kremlin troops for control of the eastern Donbas region and seek to end the war this year — a goal that requires more air and missile defenses, early warning systems, ammunition and other equipment — defense officials and experts alike say a faster influx of such lethal aid can more quickly bring a close to the conflict. 

The extent to whether that is realistic, however, is up for debate. 

The U.S. and its European allies and partners, have attempted to keep pace with Ukraine’s pleas for more weapons, with the former alone giving $7.3 billion in lethal aid to Kyiv as of this week.  

The most recent $400 million package, announced last week, includes four of the High Mobility Artillery Rocket System, or HIMARS. The truck-mounted systems can fire multiple armaments that are satellite-guided, allowing the Ukrainians to more precisely hit targets at a range of more than 40 miles — further than any artillery system previously given to the Ukrainians.  

HIMARS — 12 of which have now been pledged to Ukraine since last month — have given its forces a boost in its fighting, which for the last few months has centered on a battle for control of its easternmost region that has ground to a stalemate with Russia making small advances. 

But the rocket systems have helped with the stall, with the country’s defense minister tweeting this past weekend that the deployment of HIMARS has “already made a HUUUGE difference on the battlefield.” 

“More of them as well as [American] ammo & equipment will increase our strength and help to demilitarize the terrorist state,” he added. 

The Ukrainians have used the system to hit some 20 Russian ammunition depot targets since acquiring the systems in the last few weeks, according to media reports, making it apparent the equipment is working effectively in the battle. 

Though four of the launchers are currently being used by U.S.-trained Ukrainian troops — with four additional expected to make it to the country this month — it’s still far less than the up to 300 multiple-rocket launchers Ukrainian officials say they need to beat back the Kremlin.  

What’s more, Russian forces have the ability to fire rounds several times over what Ukraine’s forces can manage, keeping the war in a state of attrition in the country’s industrial heartland of Donbas. 

The Biden administration, however, has held off on sending large quantities of offensive and defensive rocket systems along with other high-tech equipment, wary that the systems may be too complicated for Ukrainian forces to learn to operate and maintain on the fly, according to Mark Cancian, a former Pentagon official now with the Center for Strategic and International Studies.  

Typical courses to teach how to operate such systems usually take months but have been squeezed down to three weeks for the Ukrainians, a very abbreviated timeline.  

“I think the administration in fact, I know that they don’t want to send equipment over before the Ukrainians are ready to maintain and operate,” he told The Hill.  

That theory has since been partly debunked after a senior U.S. defense official told reporters last week that the Pentagon found it “impressive” how fast Ukrainians have learned how to operate and deploy the HIMARS. 

Another holdup, Cancian noted, is the fear that if equipment goes over too quickly it can’t be maintained. 

“I think also the administration is concerned that at some point … someone’s going take a picture of a field full of junked equipment that the Ukrainians couldn’t maintain anymore,” he said. “I think that is what’s causing the administration to pace what it provides out.”  

Even with Western commitments, Ukrainians still don’t have enough weapons to end the war anytime soon against the Russians, who could still dip into their reserves to cut through the stalemate in the Donbas, according to former Supreme NATO Commander retired Gen. Wesley Clark.  

“With Russian reserves being formed up, some 20 to 40 battalion groups have been held back, there could be a strategic breakthrough,” Clark said on CNN last week. “That breakthrough . . . could be the key to getting the Ukrainian army defeated in Donbas.” 

And the Kremlin has time on its side, the Finnish ambassador said earlier this week, predicting that Russia could fight for “a very long time,” as U.S.-led sanctions on Moscow because of the attack probably won’t weaken its forces for up to a year. 

NATO Secretary-General Jens Stoltenberg also said in June that the alliance must be prepared for the war to drag on for “years,” adding that if more modern weapons are given to Kyiv and soon it would up its chances of being able to push the Russians from the Donbas. 

Stoltenberg’s assessment of a long war has since been backed up by Russian President Vladimir Putin’s move Thursday to sign a law allowing his government to introduce special economic measures to support Moscow’s forces during “counter-terrorism and other operations.” 

What’s also concerning, after nearly five months of war cracks have begun to show among the U.S., and its European and global partners as countries become affected by domestic pressures and crises, including runaway inflation and energy prices, fears of a recession and political pressure.  

A war of attrition in Ukraine could reach beyond the world’s capacity to keep the focus on providing support for Kyiv, regional watchers warn.