European militaries are emptying their arsenals to send heavy-duty howitzers to Ukraine

• The US and European countries have sent scores of artillery pieces to Ukraine.
• A few countries have sent most or all of their artillery arsenals to help Kyiv fight Russia.
• Those militaries now face the challenge of supplying Ukraine while keeping their own forces armed.

The US and European countries have sent scores of artillery pieces to Ukraine. A few countries have even sent most or all of their artillery arsenals. The question now is how many cannons and how many rounds can they give and still keep their own forces armed.

For example, France announced in January that it would be delivering another 12 Caesar truck-mounted 155 mm howitzers to Ukraine, on top of the 18 it has already sent. That's more than one-third of France's inventory of 76 Caesars.

Also in January, Denmark pledged to send the nine Caesars that it slated to get from France onto Ukraine within the next six months. Estonia has promised to transfer all 24 of its FH-70 towed 155 mm howitzers. Britain plans to send 30 of its 89 AS90 self-propelled 155 mm howitzers.

The problem is that European countries are running into the same wall faced by all the nations scrambling to resupply Ukraine. There is a limited number of weapons and munitions in stock, and ramping up production of new equipment is difficult.

But at least the US and large European militaries, like Britain, France, Germany, or even Sweden, have sufficiently large arsenals to send weapons to Ukraine while still retaining some equipment for their own forces.

For the smaller NATO countries, this is a problem — Estonia has just 192 artillery pieces, according to the 2022 edition of The Military Balance, published by the International Institute for Strategic Studies.

Of that 192, some 126 — about two-thirds — are short-range 81 mm and 120 mm mortars with a range of less than 5 miles, plus another 30 old Soviet-era D-30 122 mm howitzers with a range of 10 to 14 miles.

That means sending to Ukraine all of Estonia's 24 FH-70s — with a range of up to 19 miles — isn't just removing 13% of its artillery force. It's also taking away most of Estonia's longer-range artillery, leaving it with just a half-dozen South Korean-made K9 self-propelled 155 mm howitzers that can shoot out to 25 miles.

Sending all of the French-made Caesars originally intended for the Danish army to Ukraine has also caused a stir in Denmark.

"It is practically the entire Danish artillery that Denmark is giving to Ukraine in one blow," the Danish Broadcasting Corporation said in an article. "It is a weapon system that is the most powerful and most long-range that exists in the Danish army. It is a weapon system that people have been looking forward to and that the soldiers have been looking forward to working with."

Danish Defense Minister Jakob Ellemann-Jensen worries that transferring the Caesars to Ukraine will delay the modernization of Danish artillery affect personnel retention. "The people who are artillerymen must have something to work with," Ellemann-Jensen said.

Not that the situation is ideal for Ukraine. While desperate to get as many Western weapons as it can to offset Russian numerical superiority, the Ukrainian military must also learn to operate, maintain, and supply a bewildering variety of artillery, tanks, missiles, and other weapons.

Nor can Ukraine rely on the capacity to other nations to replenish and sustain the equipment they send, which inevitably will be destroyed in combat, require maintenance and overhaul, and need a steady flow of appropriate ammunition and spare parts.

For example, the US is scrambling to boost production of 155 mm artillery shells as Ukraine fires up to 7,000 shells a day. But expanding manufacturing capacity for artillery shells may take years, while the artillery pieces themselves may not even be in production anymore.

For the bigger military powers, this may be a temporary inconvenience as their defense industrial base gears up for a long war in Ukraine. But for smaller nations that can't make their own heavy artillery, the alternative is to import them from the handful of nations with the capacity to produce major weapons systems.

The question is whether countries such as the US, Britain, and France can simultaneously arm Ukraine, refill their own stocks, and still supply their smaller allies.

Michael Peck is a defense writer whose work has appeared in Forbes, Defense News, Foreign Policy magazine, and other publications. He holds a master's in political science. Follow him on Twitter and LinkedIn.