As this country’s biggest rivals are accumulating nuclear weapons, the U.S. claims there is a “increased potential” threat of coming nuclear warfare.

According to a newly released 2020 Pentagon study on nuclear activities, Russia and China have been upgrading and increasing their respective arsenals over the previous decade.

North Korea has escalated missile tests capable of reaching the United States, and Iran has the capacity to build a nuclear bomb within a year of deciding to do so.

Since 2010, the United States has attempted to negotiate nuclear weapons capability reductions, but “no prospective opponent has decreased either the importance of nuclear weapons in its national security policy or the quantity of nuclear weapons it deploys,” according to the report.

The study, was issued on Tuesday and explicitly cites Russia, China, North Korea, and Iran, claiming that they have “gone decisively in the other direction.”

“As a result, there is an increased potential for regional conflicts involving nuclear-armed adversaries in several parts of the world and the potential for adversary nuclear escalation in crisis or conflict.”

Along with their existing technologies and arsenals, Russia and China pose the greatest threat to the United States.

In 2019, Russia and the United States exited the 1987 Intermediate-Range Nuclear Forces Treaty, which mandated the elimination of all nuclear and conventional ground-launched ballistic and cruise missiles with ranges of 500 to 5,500 kilometers.

In 2021, the two countries agreed to prolong the New Strategic Arms Reduction Treaty (START) for another five years.

The New START deal improves U.S. national security by imposing verifiable restrictions on all Russian deployed intercontinental-range nuclear weapons.

Russia has updated its Soviet warhead delivery capabilities, utilizing new nuclear warheads and launchers, and is building three new intercontinental-range nuclear weapon systems, which it deems are the “main challenges to its present geopolitical aspirations.”

High-tech aircraft, ground-launched cruise missiles, and undersea autonomous torpedoes are among the armament systems.

China has upgraded the quantity and capabilities of its nuclear weapons, including submarine-launched missiles that are among the world’s most sophisticated.

China is also working on a bomber that will allow the country to launch weapons from land, sea, and air.

According to the U.S. assessment, North Korea has “accelerated” its pursuit of nuclear weapons and substantially boosted missile flight testing, most notably launching intercontinental-range missiles capable of reaching the U.S. heartland.

“North Korea’s ongoing pursuit of nuclear weapons capabilities poses the most urgent and serious proliferation danger to world peace and stability,” says the report.

According to the Pentagon study, Iran has the capability and capacity to create a nuclear weapon within a year of deciding to do so.

Iran’s “aggressive strategy and activities to destabilize neighboring governments, raises questions about its long-term commitment to forgoing nuclear weapons capability.”

Meanwhile, according to the 2020 study, the U.S. nuclear weapons program is a deterrent that will only be deployed in “exceptional situations” to defend the United States or its allies against assaults on population or critical infrastructure.

The language of the 2020 version was softened, and allusions of deploying nuclear weapons to “prevail in battle” were eliminated.

“Using nuclear weapons may provide circumstances for significant outcomes and the restoration of strategic stability,” according to the 2019 study, adding, “The deployment of a nuclear bomb, in particular, will profoundly alter the scope of a war and establish conditions that will influence how commanders will win in a combat.”

“Flexible and restricted U.S. nuclear reaction options can play an essential role in restoring deterrence following limited enemy nuclear escalation,’ according to the revised 2020 edition. “Limited nuclear use will create conditions that affect how commanders conduct operations.”

Russia, China, North Korea and Iran developed and increased their high-tech nuclear weapons programs since 2010

A recently released Pentagon report outlines four of the U.S.’s major enemies’ nuclear weapons capabilities.

Russia: Russian strategy and doctrine emphasize the potential coercive and military uses of nuclear weapons.

The country has upgraded its Soviet technology by developing new delivery capabilities.

The country has intercontinental-range nuclear weapon systems, including a hypersonic glide vehicle; ground-launched cruise missiles, a nuclear-armed a undersea autonomous torpedoes.

China: “China continues to increase the number, capabilities, and protection of its nuclear forces.”

It has developed its “most advanced” submarine-launched missiles and is developing a bomber, which would allow the country to fire weapons by land, sea and air.

North Korea: Over the last few years, the country has “accelerated” its pursuit of nuclear weapons and dramatically increased its missile flight testing, most recently including the testing of intercontinental-range missiles capable of reaching the U.S. homeland.

“North Korea’s continued pursuit of nuclear weapons capabilities poses the most immediate and dire proliferation threat to international security and stability.”

Iran: The country has the technology to develop a nuclear weapon within a year of when it decides to do so.

Iran’s “aggressive strategy and activities to destabilize neighboring governments, raises questions about its long-term commitment to forgoing nuclear weapons capability.”