Amid the current economic uncertainty, American Express remains strong thanks to its cardholder base, so it makes a great stock to own during good times and bad. And today, trading at only 15 times forward earnings estimates, it's a fantastic bargain for long-term investors.

Even as other billionaires watch their fortunes shrink in the recent market turbulence—with Elon Musk alone losing over $139 billion in 2025 (as of April 21), Warren Buffett's net worth has grown by $16.

Investing in the stock market has been a roller-coaster ride of late. The S&P 500 shed 2.4% on Monday as investors digested President Donald Trump's latest round of attacks on Federal Reserve Chair Jerome Powell,