It’s no coincidence that the license plate for Chicago architect Walter A. Netsch, Jr. said "WN 21." "21" stood for "21st century," symbolizing where the progressive architecture of this strong-willed maverick always was headed. Netsch's geometrically complex buildings, including the much-admired Cadet Chapel at the U.S. Air Force Academy, broke the mold of glass-box orthodoxy in the mid-20th century and helped set the stage for today's expressionistic, digital design. Yet any assessment of his work must come to terms with the fact that his labyrinthine structures could be bewildering as well as brilliant. “His buildings create wonderment, in the best and worst sense of the word,'” Chicago architect Stanley Tigerman once said.
 
Tall and thin with a booming voice, Netsch, who died at age 88 on June 15, was born on Chicago's South Side, the son of a meat-packing industry executive and a blue blood Yankee mother. He graduated from M.I.T. in 1943 and joined Skidmore, Owings & Merrill in 1947. He spent nearly his entire career at the firm, concentrating on prominent institutional projects in contrast to the commercial work pursued by fellow partner and in-house adversary Bruce Graham. “Netsch and Graham were bitter rivals,” wrote the architectural historian Nicholas Adams in the 2006 book, Skidmore, Owings & Merrill: SOM Since 1936. "Partner meetings, held every Monday morning, were deemed to be concluded when the conference room door slammed shut, and one or the other (usually Netsch) stormed out."
 
Both men had a hand in shaping Chicago's innovative Inland Steel Building of 1958, which places a column-free office tower alongside an adjoining service tower. Historians agree that Netsch conceptualized the project before moving on to the Air Force job, while Graham was responsible for its final, structurally expressive form. Frank Gehry has said that Inland Steel’s glistening stainless steel exterior helped inspire his own, far more sculptural mountains of metal.
 
Netsch broke decisively with boxy Miesian geometry in his Cadet Chapel of 1962, the undisputed centerpiece of the Skidmore-designed (and otherwise rectilinear) Air Force Academy north of Colorado Springs, Colorado. Suggesting a massed squadron of fighter jets about to shoot into the sky, the soaring, spiky chapel was built on a space frame of steel tetrahedrons and was enclosed with aluminum, the same material used for jets. Initially derided as a temple to America's military-industrial complex—worshiping there, it was said, was like going to church in a B-52—the chapel ultimately came to be seen as a successful synthesis of the Gothic and the Modern. The AIA honored it with the Twenty-Five Year Award in 1996.
 
Netsch soon developed his "field theory," whose departure point was the shifting of square shapes into a geometrically complex series of grids. At the hard-edged Chicago campus of the University of Illinois, the field theory led to such structures as the Architecture and Art Building, where rotated squares create silhouettes and maze-like floor plans. When the campus opened in 1965, critics derided it as "Fortress Illini," a Brutalist garrison that turned its back on the low-income neighborhoods around it. Students later complained that the darkened areas beneath the campus core, where a forest of columns supported elevated walkways, made students feel as if a mugger could be just around the corner. Netsch blamed the shortcomings on insufficient funding and poor maintenance. But the core and its Greek-inspired amphitheaters were demolished in the mid-1990s, replaced by a traditional college quadrangle.
 
Netsch retired from SOM in 1979 and served in the 1980s as Chicago's parks commissioner, where he decentralized city parks and moved to resurface hundreds of dilapidated playlots. In 1994, he donated nearly $1 million to the unsuccessful gubernatorial campaign of his wife, Dawn Clark Netsch, raising the money by selling a Roy Lichenstein painting that he had purchased for about $500 decades earlier.
 
By 2008, Netsch had lived long enough to witness a newfound appreciation for mid-century Modernism, including some—though certainly not all—of his own work. Many non-architects still rail against the difficulty of navigating and using his buildings. Yet a new generation of architects and critics are giving those very buildings a fresh look, captivated by their mystery and materiality. “I always enjoyed getting lost in his field theory buildings," one architecture buff wrote to me after Netsch's death, “and I worry about their future because their loss would be a blow to the world's architectural variety.”