But today's GOP makes it seem that way—which is why George H. W. Bush's EPA director is endorsing a Democrat for Congress

The Term "Republican Environmentalist" Is Not an OxymoronWhen my daughters tell people their father is a Republican environmentalist, the response is occasionally to laugh, or make a comment to the effect that he must be an endangered species.
But a Republican environmentalist, historically, is not an endangered species or an oxymoron.  Republican leadership has been responsible for enlightened environmental policies that have made our country a healthier, cleaner and safer place, often while leveraging market forces to limit costs and spur economic and technological advances.
I had the good fortune of being present at the beginning of America’s environmental awakening, over a half-century ago. I bear witness to our extraordinary success—I recall when the Cuyahoga River in Ohio was so contaminated it caught fire; when you could barely breathe in parts of Los Angeles; when you couldn’t see the night sky over the Grand Canyon; when the hole in the ozone layer threatened the planet and all of us who call it home.
Just two months ago, Congressman Roskam voted for deep cuts in the budgets of the EPA and Interior Department, slashing funds needed to protect the drinking water of 117 million Americans. He voted against tax credits and incentives for renewable energy; to eliminate Clean Water Act safeguards that protect communities from toxic pesticide exposure; and to weaken Clean Air Act restrictions on industrial air pollution. Roskam voted for an amendment to prohibit the US military from continuing to research and prepare for the effects that climate change has and will have on military installations
Roskam has referred to climate science as “junk science.”A dozen national academies of science have formally concluded that human-caused emissions of carbon dioxide are contributing to global warming. A member of Congress who calls their conclusions “junk science” is an embarrassment. 
It is for this reason that I have endorsed Peter Roskam’s Democratic opponent, Sean Casten, in this critical race.
Our environmental challenges today are daunting, and what the science tells us to expect from the changing climate threatens all of us. I worry about the planet my grandchildren, the youngest of them just four years old, will inherit. And yet I remain an environmental optimist: I believe that just as I have seen over my long career, American leadership and ingenuity can tackle any challenge. 
Americans, and particularly leading members of the Republican Party I have belonged to for decades, are holding the world back in addressing the existential threat of a changing climate. It is long past time for America to lead again on the environment, at home and on a global stage. I hope that Republicans serving in public office today will be reminded of our party’s great successes, and honor them with continued leadership and innovation.