The ongoing conflict in Ukraine has helped reimagine the rivalry between NATO and Russia, forcing the U.S. military to urgently address its aging nuclear-weapons program. But it won’t be cheap.

A congressional subcommittee meeting Wednesday heard evidence from Pentagon planners that the cost of replacing and upgrading the country's current nuclear system will be an estimated $450 billion over 10 years. It could cost less, but money-saving options— like reducing the number of submarines that deliver nuclear  weapons — would shrink the size and cost of the arsenal considerably, potentially risking U.S. national security and slashing spending on conventional weapons programs. Defense analysts said scaling back the nuclear arsenal could make the U.S. look weak and destabilize its global allies.

“Unilateral nuclear reductions would absolutely send the wrong message to Russia, China and other adversaries, by allowing them to think they could use and brandish nuclear weapons,” said Thomas Karako, a senior fellow on the international security program at the Center for Strategic and International Studies (CSIS), a Washington, D.C.-based think tank. “It would also send the wrong message to our allies, Japan, South Korea, Poland, NATO, who all rely on the ultimate backstop of the United States as a support to their own defenses.” 

Despite congressional fighting from GOP and Democrats over the U.S. defense budget in recent years, there appears to be little pushback in Washington over the estimate of the nuclear upgrade or whether it’s essential.

Principal Deputy Undersecretary of Defense for Policy Brian McKeon said during the congressional subcommittee on U.S. Strategic Forces meeting that upgrading the country’s nuclear deterrent — or building up a stockpile of weapons to prevent being attacked — was the Pentagon’s highest priority and completely essential during a period of “geopolitical uncertainty.”

Most members of Congress present at the hearing fully agreed, highlighting general bipartisan accord among the key lawmakers over U.S. nuclear powers. Flanking McKeon at the committee was Commander of Strategic Forces Adm. Cecil Haney, who said the systems should be fully upgraded because the “current global security environment is more complex, dynamic and uncertain” than ever before. He also pointed out that the country’s rivals had already committed to modernizing and expanding their nuclear capabilities and that the U.S. was obliged to match them.

However, Rep. Rick Larsen D-Wash., a member of the Strategic Forces subcommittee, remains unconvinced of the Pentagon's ability to pay for such a pricey program. “I remain concerned that the Department of Defense is preparing to undertake nuclear modernization programs without fully considering how to pay for and manage them concurrently," Larsen told International Business Times. "We need a clear, feasible and affordable plan to manage the potential bow wave of spending as the programs reach maturity in the 2030s.” 

While the cost will be spread out over 10 years, accounting for about 5 percent of the country’s defense budget each year, the upgrade will likely see other conventional weapons in future budgets being dropped. It’s difficult to predict what specific elements of any future defense would face cuts, but McKeon pointed out during his testimony that the upgrade would probably hurt conventional U.S. forces, such as orders of aircraft and ships. 

There have been varying reports outlining the cost of replacing the country’s nuclear forces in the last few years, with one predicting costs to run as high as $1 trillion over the next 30 years. But there are alternatives.

An August report from the Center for Strategic and Budgetary Assessments (CSBA), a non-partisan Washington, D.C., think tank, outlined areas in which the Pentagon could save money when upgrading the nuclear-weapons system. Some of the biggest savings that could be made between now and 2019 came in the form of cutting the number of ballistic missile nuclear submarines from 14 to 10, saving $8.1 billion, and eliminating the B61-12 nuclear bomb program to save $6.3 billion.

Despite the potential for savings, Evan Montgomery, a senior fellow at the CSBA and author of August’s report, told IBT via email that Russian presence in the Baltic enclave of Kaliningrad, where it had placed medium-range ballistic missiles, was a concern that means it's unlikely  Congress will decide to cut costs.

“The renewed threat from Russia is just one reason why additional reductions in U.S. nuclear weapons don't make much sense right now, but it might be the biggest,” said Montgomery. “At a time when Moscow is modernizing its own nuclear forces, violating the 1987 Intermediate-Range Nuclear Forces Treaty, and creating instability throughout its neighborhood, it’s hard to imagine that unilateral reductions wouldn’t provoke a backlash in Congress.” 

But it’s not just the external threats that are pushing modernization. Since May 2013 the military has been faced with a number of revealing investigations into widespread security lapses and complacency among the Air Force sector of the U.S. military strategic forces, some parts of which date to the 1950s. Two Pentagon studies from late 2014 outlined problems with leadership, personnel and the operation within the strategic forces.

The report mentioned drug abuse, cheating on exams and low morale and cited a bizarre story that missile maintenance crews across the country only had one specialized wrench between them to attach warheads to missiles. The wrench was sent via FedEx from base to base when required.

While these revelations clearly furthered the need to fix issues inside the deterrent forces, they apparently pale in comparison to threats from Russia, China and North Korea, which the congressional subcommittee claimed Wednesday were justifications for fully funding the upgrade and future replacement of the weapons and their accompanying delivery systems.

But not everyone agrees with that assessment.

John Isaacs, acting executive director of the Center for Arms Control and Non-Proliferation in Washington, D.C., claims that the U.S. military planners are using outdated Cold War thinking when rationalizing their decisions to replace the nuclear deterrent and are wrong that nuclear weapons will influence Russian, Chinese and North Korean behavior.

“Unfortunately, nuclear weapons experts are going back to the days when we’d say, ‘Oh, the Russians and Chinese are building so we need to build to,’” said Isaacs.

“There’s also no connection between Russian intervention in Ukraine, Crimea or Chinese expansionism in Asia to the need to build more nuclear weapons. The U.S. has thousands of weapons, and it’s done little to change behavior of our rivals so far,” he said.