Wall Street bull Tom Lee told CNBC on Thursday he's buying stocks, saying President Donald Trump's trade fight with China and key trading partners will ultimately benefit the United States.

"We don't necessarily have to view this as a net negative," the co-founder of Fundstrat Global Advisors told "Squawk Box." "It's a real attempt to sort of fix some of the imbalances that have been taking decades" to happen.

He continued, "I think the economy is quite strong. We would use any of these pullbacks to buy and add to exposure."

Trump is attacking what he sees as unfair trade on a number of fronts. His moves have been met with retaliatory measures from the European Union, Canada, Mexico and China.

Stock futures were sharply lower Thursday after Trump proposed a 25 percent tariff on $200 billion in Chinese goods. He had previously proposed a 10 percent tariffs for those goods. The Dow Jones Industrial Average was set for a triple-digit loss at the open after falling for three of the past four trading days.

No particular Chinese action led to the president's recommendation, said a senior administration official, who declined to be named, on a conference call with reporters.

In response to the threat, China said it is "fully prepared and will have to retaliate to defend the nation's dignity and the interests of the people."

Despite the market response Thursday, Lee said it maybe the right time for the U.S. to work on trade.

"If interest rates are rising plus we feel like we've reached the limits of globalization, maybe renegotiating trade is the right strategy," he said.

Lee, managing partner and head of research at Fundstrat, worked as J.P. Morgan's chief equity strategist from 2007 to 2014. He has 25 years of experience in equity research and has been one of Wall Street's biggest bulls.

—CNBC's Jacob Pramuk contributed to this report.