Russia's invasion of Ukraine has largely been a ground offensive, according to reports from the past 2½ months.

According to a New York Times report, a senior Pentagon officials says the Russians have failed to establish air superiority over Ukraine; and in many cases, Russia has "already expended" many of its most accurate weapons, such as cruise missiles and short- or medium-range ballistic missiles.

An example of Russia's depleted air force: Citing the Times report, from Feb. 24 to May 2, the Pentagon says Russia fired 2,125 missiles. According to Ben Wallace, Britain's defense secretary, the Russians' missile usage "dropped sharply" in early March.

The Russians "have blown through" many of their precision-guided munitions, said the senior U.S. official, who was not permitted to speak publicly to the Times. "In fact, they continue to hit Mariupol with a lot of 'dumb' bombs."

"Dumb" bombs — or unguided missiles — might be viewed as pre-9/11 relics for the United States and other NATO countries.

Over the last 20-plus years, Western military units have "almost completely converted their arsenals" with lasers or GPS satellite signals, according to the Times.

The unidentified Pentagon official said the multination sanctions levied against Russia have limited the Kremlin's access to electronic components needed to construct guided weapons.

Also, citing various Times interviews with senior U.S. defense officials, the Russian pilots are "unable to quickly locate and engage targets on the ground," which might account for the inefficiency of Russia burning through its munitions stockpile early in the war.

The Pentagon official asserts the Russians' best success occurs with "fixed targets" like military buildings or dense population centers, through the usage of artillery shells or rocket attacks. On the contrary, large guided ballistic missiles and air-launched cruise missiles "often fail or are inaccurate."

Before the mid-1980s, the Soviet Union was "relatively uninterested" in developing guided weapons for its air force.

Citing the Times report, the U.S. intelligence official said the Russian warplane design favors cheap mass production over accuracy and "required much less assembly before flight," thus making the less sophisticated missiles more amenable to flight crews that lack highly technical expertise.

Russia's guided munitions are "limited to air-launched Kh-101 cruise missiles deployed from Tu-95 Bear and Tu-160 Blackjack bombers flying in Russian and Belarusian airspace; ground-launched short- and medium-range ballistic missiles like Tochka and Iskander; and a small number of Kalibr cruise missiles fired from warships at sea," the official told the Times.

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