Look across the Atlantic today and you might spot the U.S. military’s future.

As the Pentagon prepares to cut spending, the British Defense Ministry is apparently well on its way toward slashing its budget, with plans to reduce the size of its Army to levels not seen since around the 19th century.

The British defense secretary is expected to announce that the army will shrink from its current size of about 100,000 regular, active-duty troops to about 84,000 by 2020 as part of a radical restructuring, according to British news reports. The last time the force was that small was during the Boer War of 1899-1902.

British officials, meantime, plan to shift more training and resources to reserve forces.

Germany, for its part, announced earlier this year that it could reduce the size of its armed forces from 240,000 to 180,000 personnel. It also announced it would suspend the draft.

The Pentagon is in the midst of its own comprehensive review to identify cuts and meet the Obama administration’s request to trim $400 billion from the defense budget over the next 12 years.

It’s unlikely that any shrinking of the U.S. military will be as drastic as has been the case in Europe. But former defense secretary Robert M. Gates, before leaving office, warned that the country’s bleak fiscal outlook would probably force the Pentagon to reduce the size of the military to some extent.

He also warned against a hollowing-out of the force — a mantra picked up by his successor, Leon Panetta.

“I’ve said repeatedly that I’d rather have a smaller, superbly capable military than a larger, hollow, less-capable one,” Gates said in May.

On Friday, Ashton Carter, the undersecretary of defense for acquisition, technology and logistics, said that Pentagon officials know they will face difficult choices about spending cuts and that the military’s pre-existing mind-set — in which the Defense Department “could always reach for more money” — can no longer apply.

But Carter suggested that there should be ways to find some savings without slashing personnel or weapons systems.

“What we would like to do as we deal with the circumstances of a smaller budget is make capability and force structure and strategic choice the last thing you get to in a budget drill and not the first thing you get to,” he told an audience at the Brookings Institution.

He noted, for example, that, for every 30 cents the Pentagon spends on developing and acquiring weapons systems, it spends 70 cents maintaining them. For every 45 cents the Pentagon spends on goods such as planes and ships, it spends 55 cents on services.

Said Carter: “These are the parts of the defense budget that are, so to speak, below the water line, but they’re very substantial.”