Julián Castro is the first 2020 presidential candidate to roll out a comprehensive plan for animal welfare, an issue that’s increasingly attracting American voters’ concern.

The Democrat’s Protecting Animals and Wildlife (PAW) plan, released on Monday, includes an array of bold proposals, including making animal cruelty a federal crime.

Castro frames his plan as a way of sticking it to President Donald Trump and as the solution to Trumpian problems. The PAW plan would strengthen the Endangered Species Act, which Trump has weakened. And it would stop Americans from importing animal trophies that result from big-game hunting — something Donald Trump Jr. is known to love.

“The president does not care about animals and his cruel actions prove it. He has put corporate profits over living creatures and individual fortunes over our future,” Castro said. “This groundbreaking plan will improve the treatment of animals around the country and the world, and undo Donald Trump’s damage.”

Castro also seeks to reform factory farming by creating minimum standards for animal welfare and opposing state “ag gag” laws that hide animal cruelty from the public; to end the euthanasia of healthy cats and dogs in shelters; to prohibit the testing of cosmetics on animals; and to protect at least 30 percent of US lands and oceans by 2030.

Animal welfare advocates, including the Humane Society Legislative Fund and Animal Wellness Action, were quick to praise the PAW plan and urged other candidates to follow Castro’s lead. Several of the Democratic candidates have already been very public about their concern for animals — including Rep. Tulsi Gabbard and Sen. Cory Booker, both vegans.

But none of them have released a detailed set of proposals like PAW — and that may be to their detriment. Castro’s plan is not only compassionate toward animals and the planet; it’s also smart politics.

Americans are increasingly concerned with animal welfare. The incredibly rapid embrace of plant-based meat products like Impossible Burgers and Beyond Meat is, in part, attributable to a growing sense that we can and should be inflicting far less suffering on animals.

A 2015 Gallup poll found that 62 percent of Americans said animals deserve some legal protections. Another 32 percent — nearly one-third — expressed an even stronger pro-animal stance, saying they believe animals should get the same rights as people. In 2008, only 25 percent voiced that view.

It seems more and more Americans are coming to see animals as part of our moral circle, the imaginary boundary we draw around those we consider worthy of ethical consideration. Castro, aware of that trend, is leveraging it to the advantage of animals — and his candidacy.

Is it misguided to worry about animals when so many humans are suffering?

Upon hearing of a plan like Castro’s, some people will inevitably react with a bout of “whataboutism.” They may feel perplexed or even incensed that Castro is spending a lot of time thinking about animal suffering — what about urgent human problems like homelessness and poverty and mass incarceration?

Underlying this objection is typically a sense that we can’t afford to “waste” compassion on animal suffering, because every bit of caring we devote to that cause means we have less to devote to human suffering.

But as Vox’s Ezra Klein wrote, new research from Harvard’s Yon Soo Park and Dartmouth’s Benjamin Valentino showed that concern for human suffering and concern for animal suffering is not zero-sum — in fact, where you find one, you tend to find the other:

In one half of the study, they used General Social Survey data to see whether people who supported animal rights were likelier to support a variety of human rights, a test of whether abstract compassion is zero-sum. Then they compared how strong animal treatment laws were in individual states to how strong laws were protecting human beings, a test of whether political activism is zero-sum. The answer, in both cases, is that compassion seems to beget compassion. People who strongly favored government help for the sick “were over 80 percent more likely to support animal rights than those who strongly opposed it,” the authors write. The finding held even after controlling for factors like political ideology. Support for animal rights was also correlated — though the size of the effect was smaller — with support for LGBT individuals, racial and ethnic minorities, unauthorized immigrants, and low-income people. Similarly, states that did the most to protect animal rights also did the most to protect and expand human rights. States with strong laws protecting LGBT residents, strong protections against hate crimes, and inclusive policies for undocumented immigrants were much likelier to have strong protections for animals.

The question of why these correlations exist is up for debate, but the bottom line is that we’d better hope our political system takes action on animal suffering: If it does, we’re more likely to see it taking action on human suffering too.

That makes Castro’s animal welfare plan something to celebrate — and perhaps, for other presidential candidates out there, something to emulate.

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