Immigration reform has been a hot-button issue long before President Trump pledged to build a wall along our border. And while there's certainly an argument to be made that we need to do a better job of controlling illegal immigration, there's also a strong case to be made that immigrants are a big driving force behind America's growth -- past, present, and future.

Warren Buffett has been very outspoken in recent years about America and its amazing economic story. Not only does Buffett feel that immigrants have led us to where we are today, but he also thinks that immigrants are an essential component of our country's future success.

Warren Buffett speaking to the media.

Image Source: The Motley Fool.

Here's what Warren Buffett thinks of immigrants

In a nutshell, Buffett feels that immigrants (including undocumented ones) have been and continue to be a key part of our prosperity -- not a part of the problem. "This country has been blessed by immigrants," Buffett said in February at Columbia University. "You can take them from any country you want, and they've come here and they found something that unleashed the potential that the place that they left did not, and we're the product of it."

Referring to Albert Einstein and Leo Szilard, both of whom were immigrants themselves, Buffett said, "If it hadn't been for those two immigrants, who knows whether we'd be sitting in this room."

In his most recent letter to Berkshire Hathaway's (BRK.A -0.76%) (BRK.B -0.69%) shareholders, Buffett specifically mentioned immigrants as one of the major components of America's success story. "From a standing start 240 years ago -- a span of time less than triple my days on earth -- Americans have combined human ingenuity, a market system, a tide of talented and ambitious immigrants, and the rule of law to deliver abundance beyond any dreams of our forefathers."

On a pathway to citizenship

Buffett is an outspoken Democrat who actively campaigned for Hillary Clinton during the 2016 presidential race. So it shouldn't come as too much of a surprise that Buffett doesn't want to deport millions of illegal immigrants who are currently in the United States.

In a 2015 interview with Fox Business, Buffett said

People should be able to earn citizenship who are here. You know, I do not think we should deport millions of people. So, I think we should have a real path to citizenship.

Buffett was then asked specifically about the DREAM Act and its 800,000 minors who are in the country illegally and now face an uncertain future after the end of DACA, from the perspective of a successful American businessman. Buffett replied:

It is a question of being a human being not really a businessman. Immigrants came, our forefathers came as immigrants, they got here anyway they could. And who knows what I would have done if I were in some terrible situation in a country and wanted to come here...a great percentage of them are good citizens. I would have a path to citizenship for them, I would not send them back.

On immigration policy and reform

As we all know, the immigration debate has been going on for a long time. And Buffett's stance hasn't changed much over the past several years. In a 2013 interview with ABC's This Week, Buffett said:

I think we should have a more logical immigration policy. It would mean we would attract a lot of people, but we would attract the people we want to attract in particular -- in terms of education, tens or hundreds of thousands of people. We enhance their talents and have them stick around here.

Buffett went on to say that any reform package should "certainly offer [undocumented immigrants] the chance to become citizens," and one main reason for doing so would be to deepen the talent pool of the labor force.

Buffett's stance on immigration in a nutshell

Warren Buffett believes that allowing immigrants who are already in the country to stay and pursue citizenship is not only the right thing to do, but is essential to America's continued economic prosperity. Buffett certainly sees the need for immigration reform, as most Americans of all political affiliations do, but wants to encourage and simplify the legal pathways to immigration.