Warren Buffett is celebrating the successes of Berkshire Hathaway’s companies last year and in the 60 years since he took over a struggling New England textile company and began converting it into a massive conglomerate.

COLUMN. In his annual letter to shareholders published on Saturday, the Berkshire Hathaway boss urged the US president to spend government money 'wisely,' and warned him of the inflationary crisis that could result from his policies,

As always, Buffett shared insight into Berkshire's operations and plenty of wisdom. However, this time he also revealed something that could be concerning to shareholders if you connect the dots. Buffett just identified the biggest threat to Berkshire Hathaway.