Mounting concerns over the evolving global nuclear order dominated testimony on Capitol Hill as United States intelligence chief Tulsi Gabbard warned that five countries—Russia, China, North Korea, Iran and Pakistan—pose the most significant strategic threat to US security through advancing nuclear capabilities and delivery systems.Appearing before the Senate Intelligence Committee, Gabbard outlined the findings of the 2026 Annual Threat Assessment, stressing that a combination of modernised arsenals, hypersonic technologies and evolving military doctrines is reshaping deterrence dynamics. She told lawmakers that these states are actively refining systems capable of delivering both nuclear and conventional payloads over long distances, with several platforms able to reach US territory or critical allied infrastructure.
Russia remains at the centre of the assessment, with intelligence officials highlighting its vast nuclear stockpile and continued investment in next-generation delivery systems. Gabbard noted that Moscow’s development of hypersonic glide vehicles and nuclear-powered cruise missiles reflects a strategic emphasis on bypassing missile defence systems. Analysts believe such technologies complicate early warning and interception, reducing response time in the event of a launch.
China’s rapid expansion of its nuclear arsenal has emerged as another key concern. The report points to Beijing’s efforts to diversify its delivery platforms, including land-based intercontinental ballistic missiles, submarine-launched systems and air-delivered weapons. Intelligence estimates suggest China is moving towards a larger and more flexible nuclear force designed to ensure survivability and second-strike capability, marking a shift from its traditionally smaller deterrent posture.
North Korea continues to advance its ballistic missile programme despite sanctions and diplomatic isolation. Gabbard told lawmakers that Pyongyang has demonstrated increasing range, accuracy and payload capacity in its missile tests. Its pursuit of solid-fuel ICBMs and manoeuvrable re-entry vehicles is viewed as an effort to improve launch readiness and evade missile defence systems, raising concerns across the Korean peninsula and beyond.
Iran’s nuclear trajectory remains under close scrutiny, with intelligence officials noting that while Tehran has not formally crossed the threshold of weaponisation, it retains the technical capability to do so if it chooses. The report emphasises the country’s progress in uranium enrichment and missile development, particularly medium-range systems capable of striking regional targets. Gabbard indicated that Iran’s strategic calculations are influenced by regional tensions and its desire to maintain deterrence against perceived adversaries.
Pakistan’s inclusion in the assessment reflects longstanding concerns about nuclear stability in South Asia. While Islamabad’s arsenal is primarily viewed as a deterrent against neighbouring rivals, the report highlights risks linked to command-and-control security, the expansion of tactical nuclear weapons and the potential for escalation during crises. Intelligence officials continue to monitor developments in the region, particularly as geopolitical competition intensifies.
Beyond individual countries, Gabbard underscored a broader shift in the global security environment. The convergence of nuclear and conventional capabilities, coupled with advances in cyber warfare and space-based assets, is blurring traditional boundaries in conflict scenarios. She warned that adversaries are increasingly integrating nuclear signalling into conventional military strategies, raising the risk of miscalculation.
Lawmakers from both parties pressed intelligence officials on the implications for US defence planning. Questions focused on the readiness of missile defence systems, the resilience of critical infrastructure and the credibility of extended deterrence commitments to allies. Gabbard responded that while the United States maintains a robust nuclear triad, the pace of technological change among rival states requires sustained investment and strategic adaptation.
The assessment also points to a growing emphasis on hypersonic weapons across multiple countries. These systems, capable of travelling at speeds exceeding Mach 5 while manoeuvring unpredictably, present challenges for existing detection and interception frameworks. Defence experts argue that such capabilities could undermine traditional deterrence models by compressing decision-making timelines for national leaders.
Diplomatic dimensions featured prominently in the discussion, with some senators urging renewed arms control efforts to manage the evolving threat landscape. Gabbard acknowledged the role of international agreements but cautioned that strategic competition and mistrust among major powers complicate negotiations. The erosion of earlier arms control frameworks has added uncertainty, particularly as emerging technologies fall outside existing treaties.