In the months since the novel coronavirus started spreading across the world, Bill Gates has been one of the most outspoken public figures with regards to the global response to the pandemic.

However, Gates says he wishes he had "done more" to warn the world about the potential dangers of a global pandemic before coronavirus became one of the biggest public health issues in decades. The pandemic has already killed nearly 290,000 people globally, including more than 80,000 in the U.S.

"I wish I had done more to call attention to the danger," Gates said in an interview with The Wall Street Journal published Monday.

To be fair, in addition to being a regular presence in television and podcast interviews about the pandemic in recent months, the billionaire and Microsoft co-founder was also on the record with warnings about the grave dangers presented by mass pandemics years before the Covid-19 outbreak.

For instance, Gates gave a TED Talk speech in 2015 warning people that an infectious virus was a greater risk to humanity than nuclear war, and he regularly called for world governments to step up their pandemic response plans.

(And Gates and his wife Melinda even shored up their own pandemic plans. "A number of years ago, we talked about, 'What if there wasn't clean water? What if there wasn't enough food? Where might we go? What might we do as a family?'" Melinda Gates told BBC Radio Live in April. "We had prepared, and had some food in the basement in case needed....")

Still, Gates now says he wishes he'd been more outspoken to successfully convince world leaders about the potential for a "once-in-a-century pathogen" — which he now believes SARS-CoV-2 to be — to wreak havoc on the world.

"I feel terrible," he told the Journal. "The whole point of talking about it was that we could take action and minimize the damage."

Instead, Gates has been unsatisfied with government responses to the pandemic, which he predicted in one recent interview will end up costing the world "tens of trillions of dollars." The billionaire has been particularly critical of the U.S. response to coronavirus.

In March, Gates said the U.S. "did not act fast enough" in its response to the pandemic to avoid taking extreme measures, such as shutting down businesses and issuing stay-at-home orders to millions of Americans. And, in April, Gates chimed in with his belief that President Donald Trump's decision to defund the World Health Organization (WHO) is "as dangerous as it sounds." 

Gates' critical comments, as well as his years-old comments about the dangers of a global pandemic, have even put him in the cross-hairs of conspiracy theorists — some of whom have made unfounded claims that he's seeking to profit from the pandemic, or that he knew about coronavirus years before it appeared, or even that he wants to implant the global population with vaccine microchips.

Meanwhile, the billionaire has also put his philanthropic efforts to work to help combat the pandemic's spread. The Bill & Melinda Gates Foundation has already committed more than $300 million to help fund the development of coronavirus treatments and vaccines.

"I'm putting hundreds of millions of the foundation's money into this," Gates told the Journal. "But it's really a governmental thing, just like the defense budget is there to help with an outbreak of war."

While Gates says that many of the world leaders he spoke to about the dangers of a large-scale viral outbreak were sympathetic to his argument, he still wishes he'd been able to convince them to act sooner and put strategic plans into place that would accelerate the development of treatments and vaccines in the event of a pandemic.

"I wish the warnings that I and other people gave had led to more coordinated global action," he said.

Gates added: "My hope now is that leaders around the world, who are responsible for protecting their citizens, will take what has been learned from this tragedy and invest in systems to prevent future outbreaks."

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