The public-private partnership that funded the nearly three-year, $15 million effort to fix the earthquake-damaged Washington Monument should be a model for future projects, billionaire David Rubenstein said in a CNBC interview Monday—the day the iconic obelisk reopens to visitors.
Rubenstein matched the federal funding of $7.5 million to expedite the renovation, following damage from a rare D.C.-area quake in August 2011.
"I think the Washington Monument is a symbol of our country in many ways, and it's a beacon to liberty and a beacon to freedom, and therefore I thought it was a good thing to support," the co-founder of private equity giant The Carlyle Group said in the interview with "Squawk Box."
"I initially said I would put up all the money. Then I think the parks service felt it should be done as a public-private partnership because Congress thought it should have some role."
"I thought that was appropriate," he continued, "because public-private partnerships are something that has to be done in the future. The federal government doesn't have the money to do everything it would like to do, and can't do everything it did in the past."
The memorial to George Washington was built in two phases between 1848 and 1884. When completed, it had been the world's tallest structure for five years until the Eiffel Tower in Paris came along. The iconic obelisk normally draws about 700,000 visitors a year.
Rubenstein mum on Beats rumor
While standing in front of the Washington Monument, Rubenstein also commented briefly on Carlyle's stake in Beats Electronics, which Apple is said to be interested in buying for $3.2 billion.
"I obviously can't say anything until there's an official announcement. And I can't say when or if there will be," he said. "I can only say it's a terrific product."
He said Carlyle bought a $550 million stake in Beats in September—calling it a "very good" investment. "I can't tell you anything more than that without going to jail," he added.
The headphone and music streaming company, co-founded by hip-hop star Dr. Dre and music producer Jimmy Iovine, is valued at about $1 billion. The PE group stands to triple its investment, if Apple does indeed buy Beats.
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Many analysts were scratching their heads about why Apple would want to buy Beats. Some speculation centers on whether this would be a really expensive way to hire Iovine, who has deep ties with Apple because of his friendship with Steve Jobs.
—By CNBC's Matthew J. Belvedere. Wire services contributed to this report.