Trump Executive Orders Target Precautionary Nuclear, Climate Rules

Two recent Trump executive orders (EOs), issued on May 23, 2025, contain detailed legal language, but behind these technical terms lie significant policy shifts confronting the precautionary principle. The orders—Restoring Gold Standard Science and Ordering the Reform of the Nuclear Regulatory Commission (NRC)—directly challenge longstanding assumptions used in regulations. Specifically, the Gold Standard Science order emphasizes transparency in assumptions, instructing government employees not to rely unnecessarily on highly unlikely or overly precautionary scenarios. The second executive order calls on the NRC to “adopt science-based radiation limits,” rather than relying on precautionary safety models that have “tried to insulate Americans from the most remote risks without appropriate regard for the severe domestic and geopolitical costs of such risk aversion.” These changes have wide-ranging implications for environmental and climate science, as well as for the energy sector.

What does this mean in practical terms?

Consider some examples from the EOs to see how scientific data impacts regulatory decisions. NOAA’s fisheries division has the authority to issue permits allowing lobster fisheries to operate. The issue at hand is that lobster fishing gear can cause the endangered North Atlantic right whale to become entangled in fishing gear, prompting the agency to prescribe a switch to ropeless fishing methods, reducing entanglement risk by 98%. However, this method involves very expensive gear upgrades, which would render the lobster industry uncompetitive. NOAA’s recommendation was based primarily on whale birth rate data from 2010 to 2018, a period during which birth rates were relatively low. Data from periods before or after those dates, when whale birth rates were higher, were not considered. The Maine lobster fisheries took the issue to court. Initially, the ruling favored the regulator, but the decision was later overturned by the D.C. Court of Appeals, which concluded that “the agency’s decision to seek out the worst-case scenario skewed its approach to the evidence.”

A similar precautionary approach is seen in climate policy. The EO specifically critiques the use of the worst-case warming scenario known as Representative Concentration Pathway (RCP) 8.5, which predicts an increase in temperatures by about 8.5°F by the end of the century. Although we do not know precisely how much temperatures will rise, current science suggests that RCP 8.5 is at the high end of potential warming scenarios, and more moderate outcomes are far more likely. Unless updated by the best available science, the EO directs agencies not to base regulatory decisions on such extreme scenarios.

The nuclear EO also criticized the existing precautionary approach, asserting that a “myopic policy of minimizing even trivial risks ignores the reality that substitute forms of energy production also carry risk, such as pollution with potentially deleterious health effects.” The cost of driving risks to zero is high but often invisible—like an iceberg. What we see is the agency ostensibly protecting public health by reducing radiation exposure. What remains unseen is how such policies stifle technological advances and limit our access to clean, reliable baseload power from nuclear plants. While the U.S. currently operates the largest nuclear fleet globally, only two reactors have begun commercial operations in recent decades. Beyond domestic impacts, this trend has clear geopolitical implications as the U.S. concedes nuclear leadership to nations such as China, Russia, and South Korea.

Driving Risks to Zero is Not Prudent

Does this mean we do not care about right whales, climate impacts, or potential radiation exposure? This is a common fallacy perpetuated by those seeking to drive risks as close to zero as possible. Risk reductions always come at a cost. Just as it doesn’t make sense to reduce pollution to zero (since we still want access to goods and services), it also doesn’t make sense to drive all risks to zero. Rather than relying on worst-case scenarios, it is more prudent to find a middle ground and act based on the most likely scenarios, which usually come at a significantly lower cost.

This is not to suggest malicious intent by regulatory agencies. Rather, they are following decades-old premises rooted in precautionary principles that significantly slow permitting processes, despite occasional successes. This week, the NRC approved NuScale’s design for a 77-megawatt, 6-module small modular reactor plant. While the agency employs knowledgeable public servants, they operate under the stifling dictates of the linear no-threshold (LNT) model for radiation exposure and the “as low as reasonably achievable” standard. The LNT model assumes every bit of radiation is harmful and thus must be minimized, disregarding the cell’s capacity to repair itself after minor radiation exposure. In reality, people living in areas with naturally higher background radiation don’t show the health problems that current radiation safety models predict they should have. The executive order explicitly states that these models “lack sound scientific basis.”

Regulatory Agencies Are Slow to Change

Will agencies respond positively to the president’s directives? This is not the first time the NRC has been asked to reconsider the LNT model. Nuclear pundit Jack Devanney pointed out that “the NRC has been asked to reconsider LNT at least three times. The NRC pondered the issue for three years before proclaiming—to no one’s surprise—that it was sticking with LNT.” In other words, the nuclear EO might lack sufficient teeth to force the agencies to change their standard operating practices. Yet, as Adam Stein, Director for Nuclear Energy Innovation at the Breakthrough Institute, put it, “the executive orders say the quiet part out loud.” Stein also noted that because the NRC was merely asked to reconsider rather than explicitly abandon its precautionary models, the EOs represented a “big missed opportunity to finally align the NRC with a modern, risk-informed approach.”

Finally, the precautionary principle is widespread not just federally, but at the state level as well. For example, the Indian Point nuclear power plant, which previously supplied New York City with power, was ordered to shut down due to concerns about the health of Atlantic sturgeon in the Hudson River—not because of radiation concerns, but rather fears that cooling water from the nuclear plant could harm sturgeon eggs. The worst-case scenario was that fish populations might be damaged. Ultimately, it was New York State’s energy security, emissions profile, and local employment that were harmed.

In the end, obscure scientific concepts drive many regulatory decisions, which are often justified under the guise of protecting public health or the environment. A gold standard in science means all scientific decisions are transparent, clearly outlining assumptions, and ensuring that while worst-case scenarios are considered, they do not solely drive our policy-making.