what was the actual plan behind it?
David Rockefeller suggested that the Port Authority would be a logical choice for taking on the project. Rockefeller argued that the Trade Center would provide great benefits in facilitating and increasing volume of international commerce coming through the Port of New York and New Jersey.
Original plans
David Rockefeller suggested that the Port Authority would be a logical choice for taking on the project because it had experience with similar large engineering projects, and also because the Port Authority, rather than Rockefeller, would be paying for the complex's construction. Rockefeller argued that the Trade Center would provide great benefits in facilitating and increasing volume of international commerce coming through the Port of New York and New Jersey. David's brother, New York Governor Nelson Rockefeller, formally asked the Port Authority to investigate the feasibility of this proposal. Given the importance of New York City in global commerce, Port Authority director Austin J. Tobin remarked that the proposed project should be "the" World Trade Center, and not just a generic "world trade center". Tobin commissioned an aide, Richard Sullivan, to lead a study on the feasibility of building a World Trade Center.
when did construction start on the twin towers August 1968
In 1958, Rockefeller established the Downtown-Lower Manhattan Association (DLMA), which commissioned Skidmore, Owings and Merrill to draw up plans for revitalizing Lower Manhattan. The plans, made public in late June 1960, called for a World Trade Center to be built on a site along the East River, at the South Street Seaport, one of the Lower Manhattan ports that had seen a continuous decline in business over the past decade. The proposed complex included a exhibition hall, as well as a 50- to 70-story building with a hotel located on some of its upper floors. Other amenities would include a theater, shops, and restaurants. The plan also called for a new securities exchange building, which the Downtown-Lower Manhattan Association hoped would house the New York Stock Exchange. The Financial District of Lower Manhattan was left out of the economic boom of financial industries there, lower Manhattan also saw less economic growth than Midtown because many workers moved to the suburbs, and they found it easier to commute to midtown than to downtown
Construction of the World Trade Center Construction of the World Trade Center Construction of the World Trade Center
Original plans Original plans Original plans
Meanwhile, the Financial District of Lower Manhattan was left out of the economic boom of financial industries there. Lower Manhattan also saw less economic growth than Midtown because many workers moved to the suburbs, and they found it easier to commute to midtown than to downtown. The writer Paul Goldberger states that the Financial District, in particular, was devoid of "almost any kind of urban amenity", including entertainment, cultural hubs, or housing. Commercial industries along the ports of Lower Manhattan were also being replaced with industries elsewhere. David Rockefeller, who led urban renewal efforts in Lower Manhattan, constructed the One Chase Manhattan Plaza in a bid to bring jobs back. Rockefeller believed that the area would lose its status as the nation's financial hub if it were not redeveloped. However, the skyscraper, which opened in 1960, attracted far fewer tenants than expected.

In 1958, Rockefeller established the Downtown-Lower Manhattan Association (DLMA) . The plans, made public in late June 1960, called for a World Trade Center to be built on a site along the East River, at the South Street Seaport, one of the Lower Manhattan ports that had seen a continuous decline in business over the past decade. The site would be bounded clockwise from the south by Old Slip, Water Street, Fulton Street, and South Street, and the complex itself would be located on "a two-story platform that would supersede and displace the conventional street grid". The proposed complex included a exhibition hall, as well as a 50- to 70-story building with a hotel located on some of its upper floors. Other amenities would include a theater, shops, and restaurants. The plan also called for a new securities exchange building, which the Downtown-Lower Manhattan Association hoped would house the New York Stock Exchange.
 Meanwhile, the Financial District of Lower Manhattan was left out of the economic boom of financial industries there. Lower Manhattan also saw less economic growth than Midtown because many workers moved to the suburbs, and they found it easier to commute to midtown than to downtown. 
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Construction of the World Trade Center [SEP] Original plans
Meanwhile, the Financial District of Lower Manhattan was left out of the economic boom of financial industries there. Lower Manhattan also saw less economic growth than Midtown because many workers moved to the suburbs, and they found it easier to commute to midtown than to downtown. The writer Paul Goldberger states that the Financial District, in particular, was devoid of "almost any kind of urban amenity", including entertainment, cultural hubs, or housing. Commercial industries along the ports of Lower Manhattan were also being replaced with industries elsewhere. David Rockefeller, who led urban renewal efforts in Lower Manhattan, constructed the One Chase Manhattan Plaza in a bid to bring jobs back.