This post is part of WRI’s blog series, The Trump Administration. The series analyzes policies and actions by the administration and their implications for climate change, energy, economics and more.

At his Senate confirmation hearing this week, Rex Tillerson, the former CEO of ExxonMobil who has been nominated as the next secretary of State, provided measured and carefully crafted answers, but did little to reassure the American public that he would lead on climate change. In fact, despite numerous opportunities to affirm that climate impacts are real, and that climate change is an urgent economic and security threat to the United States, his statements were often vague and inconclusive. This should be cause for serious concern, given the mounting observed impacts of climate change, as well as the unique U.S. role in rallying a global response to ensure a safer and more prosperous future.

Here are some of Tillerson’s responses during the hearing and where they fell short:

Tillerson: “The increase in the greenhouse gas concentrations in the atmosphere are having an effect. Our ability to predict that effect is very limited.”

“I think as you indicated that there is some literature out there that suggests that [that climate change makes extreme weather events more likely]. There is other literature that says it’s inconclusive.”

Unlike some of President-elect Donald Trump’s other appointments, Tillerson recognizes that human-caused climate change is real and happening. However, his comments to the Senate Foreign Relations Committee vastly understate the case, raising questions about whether Tillerson believes the potential threat from climate change is real. There is abundant, clear, overwhelming evidence of costly effects of extreme weather and sea level rise that are being amplified by climate change that are being felt now and require an immediate response.

Each of the past three decades has successively been the warmest on record. This decade is well on its way to continue the trend, following an unprecedented third consecutive year of record global high temperatures in 2016. Sea level rise has driven increases in coastal flooding from high tides alone between 325 percent and 925 percent in locations on all three coasts of the contiguous U.S. over the last 50 years. Heavy precipitation events have increased in every region of the contiguous U.S. since the late 1950s. And according to the U.S. National Academy of Sciences, over the past 30 years, there has been a fourfold increase in the number of large and long-duration forest fires in the American West.

By taking urgent action now, the United States can help to fend off the worst consequences of climate change and save taxpayer dollars, but that will happen only if the next government takes the established science on this issue as seriously as it deserves.

Tillerson: “I don’t see it [climate change] as the imminent national security threat that perhaps others do.”

In this response, Tillerson is more direct than elsewhere in his testimony. Unfortunately, his response does not align with scientific reports or, importantly, the views of U.S. national security experts.

For example, a 2015 Pentagon report found that “Climate change is an urgent and growing threat to our national security, contributing to increased natural disasters, refugee flows, and conflicts over basic resources such as food and water.” And, in 2014, the Defense Department called climate change a “threat multiplier.” In the report, it stated “Rising global temperatures, changing precipitation patterns, climbing sea levels, and more extreme weather events will intensify the challenges of global instability, hunger, poverty and conflict.”

The Department of Defense alone has 130 installations valued at approximately $100 billion that are threatened by a predicted three-foot rise in sea levels, so the U.S. military has good reason to be concerned about the impacts of climate change and rising seas.

Tillerson: “I think having a seat at the table to address [climate change] on a global basis is important – I think it’s 190 countries or thereabouts have signed on to begin to take action. I think we’re better served by being at that table than leaving that table.”

In response to questions about whether the Paris Agreement was in America’s best interests, Tillerson repeated this carefully scripted answer of keeping our “seat at the table” several times. This could mean that he thinks the U.S. should stay in the Paris Agreement, but from his response, it was unclear whether Tillerson was referring to the Paris Agreement or only the UN Framework Convention on Climate Change (UNFCCC), the overall treaty body created in 1992 (the Paris Agreement is the action initiative finally agreed upon by the UNFCCC). Even if Tillerson was referring to the Paris Agreement, he offered no assurance that the country should continue to play a constructive role around international climate action.

If the United States left the Paris Agreement and only stayed in the UNFCCC, it would both undermine its own credibility and lose any leverage to make sure that all countries live up to their promises to act aggressively toward a common solution. No matter what, being “at the table” is not enough. The United States must go further and lean in to that table by being a productive player in international negotiations, advancing climate solutions and honoring its international commitments under the Paris Agreement and elsewhere.

Economically and politically, the United States has nothing to gain and much to lose by leaving the Paris Agreement, which is supported by the country’s most steadfast allies and trade partners. The G20, G7, Arctic Council, United Nations and other international bodies have all made climate change one of their top priorities. If the U.S. did withdraw, it would join a group of just three other countries -- Nicaragua, Syria, and Uzbekistan – that have not signed onto the Paris Agreement.

Tillerson: “If America is the only one that is willing to lead [on international climate action], then my conclusion is the rest of the world doesn’t think it’s very important.”

This statement does not reflect the level of support for climate change action around the world. The United States is hardly alone in showing leadership on climate change. The Paris Agreement was adopted by 195 countries in 2015, and went into force into force just one year later. At the climate summit in November 2016, countries issued the Marrakech Action Proclamation demonstrating a strong affirmation to uphold the goals of Paris Agreement.

China, in particular, has shown that it would lead on climate change. In November 2014, in a joint announcement with the United States, China declared that it would peak its emissions by 2030 or sooner. The country recently re-affirmed its resolve to achieve its national climate plan. The country just recently announced that it would invest another $360 billion in wind and solar by 2020. WRI’s paper NDCs One Year On showcases for many more examples of countries’ taking strong action on climate change.

The question really isn’t whether other countries are leading, but whether America will stand alongside them in confronting this global challenge.

Tillerson: “I’m not aware of anything the fossil fuel industry gets that I would characterize as a subsidy. Rather it’s simply the application of the tax code broadly that broadly applies to all industry.”

Tillerson offered this response for a question about whether he would help implement a phase-out of fossil fuel subsidies that was agreed to by the G20 in 2009.

Although members of the U.S. oil and gas industry have long denied receiving subsidies, the facts show otherwise. The reality is that tax breaks are a form of subsidy, and the sector greatly benefits from a variety of special tax codes and incentives, not available to other industries, and that saves it money at U.S. taxpayers’ expense. The United States’ self-review of fossil fuel subsidies from December 2015 found an array of such subsidies that were specific to the fossil fuel sector rather than U.S. industry at large. According to the U.S. Treasury, fossil fuel companies benefited from a total of $4.9 billion in Federal production tax provisions in fiscal 2015. In June 2016, the non-partisan Congressional Review Service estimated that the fossil fuel industry would receive incentives of $21.5 billion between 2015 and 2019.

These benefits are particularly striking, given that the oil and gas industry is over 100 years old and generates billions of dollars in revenue.

At the hearing, Tillerson came across as intelligent, cautious, and thoughtful. But if selected as America’s top diplomat, he will need to go much further to ensure that the U.S. stays in the Paris Agreement, honors its international commitments and continues to lead on climate change.