For those of you who have visited Washington, DC, the site in question is directly across from the National Air and Space Museum. Currently, there is a small vegetable garden there and a dozen or two parking spaces.
As this story shows, the effort to establish an Eisenhower memorial has become a mess. One aspect not much commented on in the piece is the inherent difficulty of the venture: this is not an all-government effort. It involves government land, a congressionally chartered entity (Dwight D. Eisenhower Memorial Commission), and private funds.*
To further complicate matters, there are the tricky District of Columbia building laws and regulations, and as this article emphasizes, there are descendents of the honoree, who have strong feelings about the aesthetics.
*P.L. 106-79, Sec. 8672 established the Dwight D. Eisenhower Memorial Commission, and authorized a $300,000 appropriation to fund the commission.