Laura Cavallaro, 36, of Warwick, Rhode Island, who served on active duty in the Marine Corps from 2001 to 2005 and on inactive duty until 2009, said she hasn't decided whether she will support Trump in the 2020 election.
The United States has become the world's biggest oil and gas producer over the last couple of years, thanks mainly to a technology-led drilling boom.
"There has never been a president who has actively pursued an agenda so hostile to the environment and public health at the behest of polluters than Mr Trump", he said.
In contrast, the American Lung Association's most recent State of the Air found air quality declining in recent years, as more cities suffer from higher levels of particle pollution ("soot") and ground-level ozone ("smog"), which increase in hot weather. He said market pressures can produce positive changes.
At the same time, he insisted on the importance of economic growth.
Trump has promoted the use of fossil fuels and tried to unwind more stringent fuel standards for vehicles.
"It is absurd for President Trump to claim any environmental credentials when his administration continues to drive a destructive pro-polluter agenda at the expense of the American people", said Ms Jill Tauber, vice-president of litigation, climate and energy at Earthjustice, which has filed 120 lawsuits against the administration. It is far more limited in scope and could let some coal-fired power plants keep operating longer.
Donald Trump says the environment is a top priority for his administration, even as it rolls back key protections such as pulling the U.S. out of the 2016 Paris Agreement.
"And that's what we're doing", Trump said during his speech at the White House.
Marcus's support of Trump is not new. "We will defend the environment but we will also defend American sovereignty, American prosperity and we will defend American jobs".
Asked why the President chose to hold the remarks and whether the Democrats' Green New Deal would be brought up during remarks, Neumayr said it was discussed when Trump spoke to his advisers about his administration's environmental actions.
He also made no mention of the intense rain and flash flooding that disrupted Washington, D.C., on Monday. The Capital Weather Gang reported "3.3 inches of rain in ONE HOUR at Reagan National" airport, calling it an "astronomical rainfall intensity".
A Montana-based cartoonist whose work features antisemitic and racist tropes has been disinvited from the "social media summit" being held at the White House on Thursday.