PEREVALNOYE, Crimea » The soldiers guarding the entrances to the surrounded Ukrainian military base here just south of the capital, Simferopol, had little in common with their predecessors from past Russian military actions.

They were lean, fit and sober. Few if any seemed to be conscripts. Their uniforms were crisp and neat, and their new helmets were bedecked with tinted safety goggles.

And there was another indicator of an army undergoing an upgrade: compact encrypted radio units distributed at the small-unit level, including for soldiers standing such routine duty as guard shifts beside machine-gun trucks. The radios are a telltale sign of a sweeping modernization effort undertaken five years ago by Vladimir Putin that has revitalized Russia’s conventional military capabilities, frightening some of its former vassal states in Eastern Europe and forcing NATO to re-evaluate its long-standing view of post-Soviet Russia as a nuclear power with limited ground muscle.

Across Crimea in the past several weeks, a sleek new vanguard of the Russian military has been on display, with forces whose mobility, equipment and behaviors were sharply different from those of the Russian forces seen in action in the brief war in Georgia in 2008 or throughout the North Caucasus over nearly two decades of conflict with Muslim separatists.

Past Russian military actions have often showcased an army suffering from a poor state of discipline and supply, its ranks filled mostly with the conscripts who had not managed to buy deferments or otherwise evade military service. Public drunkenness was common, as were tactical indecisiveness and soldiers who often looked as if they could not run a mile, much less swiftly.

Not so in Crimea. After a Kremlin campaign to overhaul the military, including improvements in training and equipment and, notably, large increases in pay, the results could be seen in the field. They were evident not only in the demeanor of the Russian soldiers but also in the speed with which they overwhelmed Crimea with minimal violence.

The Kremlin’s investment, analysts said, has revived Russia’s military, which has now shown that it can field a competent and even formidable force, and both guard the nation and project power to neighboring states.

"The development of Russian armed forces is going in two big trends, first strengthening of strategic nuclear forces, giving a guarantee that no one country in this world will try to attack Russia," said Aleksandr Golts, an independent military analyst in Moscow.

"Second, the development of these rapid deployment forces," he said, "to deal with any kind of local conflict, such as the war against Georgia, or this operation in Ukraine or anywhere."

"As a result of these reforms," Golts added, "Russia now has absolute superiority over any country in the post-Soviet space."

One Western official who analyzes military forces in the region said the differences from the past were striking. "It does seem to us that they are much more professional this time around," the official said, speaking on the condition of anonymity because he was not authorized to speak publicly. "It’s impressive."

The transformation of the armed forces has been a personal priority of Putin, who as prime minister from 2009 to 2012 and more recently in his return to the presidency, has overseen billions of dollars in new military expenditures. The military was one of the few areas of the Russian budget to receive big spending increases, along with preparations for the Sochi Olympics, the 2018 World Cup and improvements to the railroad system, which is also a military asset.

Since the start of 2012, salaries for most military personnel have roughly tripled, to between $700 and $1,150 a month for privates and sergeants a respectable amount in Russian terms. The Kremlin has also expanded housing and education benefits.

In a speech to military officers in February shortly after the raises were enacted, Putin declared, "I have always believed that military servicemen should be paid, as has always been the case in Russia, by the way, even more than skilled specialists in the sphere of economics or administration or other civilian sectors."

The spectacular rise in military spending, which is expected to increase to about $100 billion in 2016 from about $80 billion this year, even as the economy shows signs of recession, was one of the main reasons that Russia’s respected finance minister, Aleksei L. Kudrin, who was credited with steering Russia safely through the 2008 financial crisis, left the government in 2011.

Putin has been unapologetic. He has repeatedly stressed that rebuilding the military is crucial to Russia’s future.

At his direction, a comprehensive, multiagency military strategy was developed for the first time, with ambitious goals that included bringing all units to permanent combat readiness and upgrading weapons systems.

As commander in chief, Putin has also presided over unprecedented training exercises, including the largest-ever peacetime mobilization about 160,000 troops in Russia’s Far East in the summer of 2013 and an array of drills in western Russia to prepare for potential threats along the borders with Europe and the Caucasus.

"Our goal is to create modern, mobile and well-equipped armed forces that can respond rapidly and adequately to all potential threats, guarantee peace, and protect our country, our people and our allies, and the future of our state and nation," Putin said in a meeting with military leaders in February 2013.

The lightning-quick seizing of strategic installations and the surrounding of military bases in Crimea, including the base in Perevalnoye, provided a clear show of the new Russian military’s capabilities.

It was a sharp contrast to the brief war with Georgia in 2008, when Russia overwhelmed its much smaller foe on a tiny patch of ground, but also revealed the sorry state of its own forces problems that stretched back to the two military campaigns in Chechnya. (In Georgia, Russian military vehicles were commonly seen broken down on the roads, cursing soldiers beside them.)

"First of all, there were communications problems, because the communication is the basis of troop management," said Mikhail Khodaryonok, editor-in-chief of Military-Industrial Courier, a weekly newspaper focused on the Russian armed forces.

"Problems with communications were so obvious that sharp measures were taken to improve all types of communications, including the confidential communication," Khodaryonok said.

The upgrade was visible down to the smallest unit levels in Crimea. Here at Perevalnoye, many soldiers on guard duty wore new push-to-talk encrypted radios – a piece of equipment long used by U.S. soldiers but only recently provided to conventional Russian units.

The Western official said the wide distribution of the encrypted radios suggested more than procurement. It might also mean that Russian noncommissioned officers were exercising more tactical latitude and decision-making, a deeper type of reform that could make Russian units more nimble and effective.

"That is a rather empowering device for the Russian army," the official said.

The radios were one part of a broad element of Putin’s military overhaul: the replacement of equipment carried by individual soldiers. Known as the "Ratnik" program from the Russian word for "warrior" the upgrade includes new helmets, flak jackets with bulletproof plates, ballistic goggles, kneepads, uniforms and communications and navigation equipment, as well as thermal and night-vision sights for firearms.

Apparently modeled after the equipment upgrades visible on Western soldiers in Afghanistan and Iraq for more than a decade, the Ratnik kit has not yet been fully fielded. But many of its signature components were evident in Crimea, including the uniforms, helmets, goggles, flak jackets and kneepads.

Out on the roads, Russian forces could also be seen deploying electronic-warfare platforms, including the new Tigr-M and the R-330Zh jamming station, which can block GPS and satellite telephone signals.

Like many of the Russian military vehicles visible in the crisis, these vehicles contrasted with those seen in Georgia or the North Caucasus in that they had fresh paint jobs and new tires, and seemed to be in an excellent state of repair.

While analysts said that there was now better equipment and training throughout the Russian military, some cautioned against drawing too broad a conclusion based on the forces in Crimea, many of whom were part of elite units that were among the first the benefit from the overhaul.

"It is certainly a step up from where they were in 2008, but how far of a step up we don’t know yet," said Dmitry Gorenburg, a senior analyst with the Center for Naval Analyses, a Virginia-based research group financed by the U.S. government. "Is the Russian military now a conventional threat to NATO? I don’t think so. I don’t think it’s that much of an improvement yet. It could be down the road."

Gorenburg noted that the Russian troops had faced no opposition, and that there had been no fighting. "Essentially they were taking over facilities and buildings from troops that had been given no orders or who had been given orders not to resist," he said. "There was no actual combat."

Khodaryonok, the editor of Military-Industrial Courier, said it would be awhile before the modernization campaign spreads to all the armed forces. Nevertheless, he said, the military had made extraordinary strides.

"Everything is order," he said. "There is no more such shame as broken tanks and APCs on the road and outdated weaponry."

More important, he said, the military was able to make it all work. "The biggest achievement, in my opinion, is how the management was organized," he said. "The operation’s cover, its quickness and suddenness. There were no data leaks."

"The epoch of decay has been fully overcome," he said. "And the armed forces of the country are on the rise."

© 2014 The New York Times Company