Adding to the massive wave of outrage sparked by President Donald Trump's "stupid and reckless" decision to withdraw from the Paris climate accord, Sen. Elizabeth Warren (D-Mass.) on Thursday denounced the move as a "big gift to Republican donors" at the 'Joyous Persistence' rally in San Francisco.

In response to critics like Warren and countless others, White House officials and Trump allies have attempted to defend the withdrawal by characterizing it as part of a broader plan to protect American jobs and spur economic growth.

"This is really about big donors to the Republican party."

—Sen. Elizabeth Warren

Warren, a leader of the progressive wing of the Democratic Party who is widely viewed as a potential 2020 presidential contender, forcefully dismissed this reasoning as a trope perpetuated in service of the donor class.

"[T]he Republicans have been framing this for a long time, jobs versus the environment," she said. "It is not. This is really about big donors to the Republican party."

For weeks, Trump was lobbied by a coalition consisting of, among others, his daughter Ivanka, Pope Francis, and Secretary of State Rex Tillerson, all of whom urged him to stick with the international community by firmly committing to the climate pact. In the end, however, it was the "big oil darlings" who won out, as the Guardian put it on Thursday.

The 22 Republican senators who signed a letter in May urging Trump to withdraw from the agreement received "a total of $10,694,284" in donations from oil, gas, and coal interests "over the past three election cycles," the Guardian added.

But, as some commentators pointed out, one did not need to look far to determine who would benefit from Trump's decision to side with big money over the climate. Attending Trump's "fact-free speech" in the Rose Garden of the White House was Thomas Pyle, the president of the American Energy Alliance. The fossil fuel industry group, as Politico reported, "has received some of its past funding from billionaire industrialists Charles and David Koch."

For Warren, this is an indication that Trump's assault on the environment is part of a larger attempt to undermine the fundamental tenets of democracy. Trump's decision, Warren said, is "symptomatic of what's wrong" with American politics. Corporate cash, she added, "slithers through Washington like a snake."

In closing, the Massachusetts senator told the crowd gathered in the Palace of Fine Arts Theatre to resist the administration and to not treat politics as "something that just happens every four years."

"We've got to be fighting every day," Warren said.