Fordham Spire would twist into the sky over Chicago’s lakefront like an oversize birthday candle, surpassing Sears Tower and the planned Freedom Tower in New York as the nation’s tallest building.

A Chicago developer proposed North America’s tallest building — the 1,458-foot Fordham Spire, which skyscraper builder Donald Trump dismissed as “insane.”

Spanish architect Santiago Calatrava designed the slender, spiraling hotel and condominium complex near Lake Shore Drive and Navy Pier. The glass-and-steel, concrete-core structure would be 115 floors and have a more than 500-foot spire.

The structure would top the 1,450-foot, 110-story Sears Tower, once the world’s tallest building. Taiwan’s Taipei 101 tower now is the world’s tallest skyscraper at 1,670 feet.

Fordham Co. Chairman Christopher Carley said lining up money for the up to $500 million Fordham Spire was easy because of Calatrava — designer of Athens’ Olympics sports and New York’s Ground Zero transportation complexes.

“Financiers are in awe of this man,” Carley told the Chicago Sun-Times.

Trump, who is building his 92-story skyscraper nearby, said he would not want to build or live in such a building given the climate of terrorism.

“Any bank that would put up money to build a building like that would be insane,” Trump told the Chicago Tribune.