Attrition of Automobiles

Definition

"Attrition of automobiles by cities" is Jane Jacobs's affirmative counter-process to "erosion of cities by automobiles": two processes determined by "which pressure wins most of the victories" between city concentration and vehicular accommodation (Jacobs 1961, p. 349). Erosion proceeds as "positive feedback" — "an action produces a reaction which in turn intensifies the condition responsible for the first action… something like the grip of a habit-forming addiction" (p. 350); Gruen's Fort Worth calculation showed the feedback arithmetically: serving projected 1970 commerce by car would require sixteen million square feet of roadbed, whose provision would spread the city thin and multiply car-dependence — "the more space that is provided cars in cities, the greater becomes the need for use of cars, and hence for still more space for them" (pp. 350–351). Against the pedestrian-separation schemes built on such arithmetic, Jacobs's finding is behavioral: "there is no absolute, immutable number of private automobile riders; rather, the numbers vary in response to current differentials in speed and convenience among ways of getting around" (p. 362). Washington Square's road closure — fought through against predictions of "frantic and frenetic congestion" — produced "no increase in traffic; most counts have shown a slight reduction," and "these cars — or some cars — disappeared into thin air" (pp. 360–362).

Attrition is therefore "not attrition of automobiles in cities but rather the attrition of automobiles by cities": tactics that "give room to other necessary and desired city uses that happen to be in competition with automobile traffic needs" — sidewalk widening, outdoor lobbies, small parks carried across streets, closed park roads, short blocks (pp. 363–364) — made selective to favor buses and trucks (William McGrath's New Haven techniques: unstaggered short signal cycles, dead-ended alternates, truck-priority lanes, pp. 365–367), and always positive: "To concentrate on riddance as the primary purpose… would be a policy not only doomed to defeat but rightly doomed to defeat" (p. 371). The book's alternative verdict is sardonic: if erosion cannot be stopped, "the purpose of life is to produce and consume automobiles" (p. 371).

Key Thinkers

• Jane Jacobs — the concept's author: attrition as policy where erosion was drift (1961).
• Victor Gruen (not yet paged — see log) — the Fort Worth planner whose ring-road scheme and 1955 feedback calculation supply the arithmetic Jacobs extends (pp. 344–345, 350).
• William McGrath (not yet paged — see log) — the New Haven traffic commissioner who "conceived several means by which already familiar traffic techniques can be used deliberately for selective vehicular encouragement and discouragement" (p. 365).
• Baron Haussmann — the ancestor-figure invoked through Moses's park-highway lineage (Sara Delano Roosevelt Park "equated as an achievement with the Rue de Rivoli of Paris," p. 76n).

Related Concepts

• mixed-primary-uses — the precondition: "Consideration for pedestrians in cities is inseparable from consideration for city diversity, vitality and concentration of use" (p. 348).
• small-blocks — the passive attrition already built into the diversity programme (p. 364).
• automobile-vernacular — the wiki's register of the vehicle-shaped built environment attrition works against.
• border-vacuums — erosion's spatial signature: "the necessary parking, garaging and access arteries around the pedestrian preserves reach such unwieldy and deadening proportions that they become arrangements capable only of city disintegration" (p. 345).
• organized-complexity — the method frame: erosion as positive feedback, the feedback concept imported into urban analysis (pp. 350–351).

Source Support

Sources in the wiki that discuss this concept:

• The Death and Life of Great American Cities (Jacobs 1961) — the concept's chapter (Ch. 18, pp. 338–371): the Nopplace opening (p. 338); the horse-city counter-history and Creswell's 1890 London (pp. 340–342); "The point of cities is multiplicity of choice" (p. 341); the erosion/attrition fork (p. 349); Gruen's sixteen-million calculation and positive feedback (pp. 350–351); Manhattan's one-way avenues and vanished bus riders (pp. 351–352); Los Angeles at 95% automobility still jammed (p. 354–355); the pedestrian-street audit (Boston, Disneyland, pp. 346–348); Washington Square's closure history (pp. 360–362); the attrition tactics catalogue (pp. 363–365); McGrath's selectivity (pp. 365–368); "The purpose of life is to produce and consume automobiles" (p. 371).
• Dark Age Ahead (Jacobs 2004) — the concept's cultural-collapse escalation and its two 1961 cases reprised as evidence: "Not TV or illegal drugs but the automobile has been the chief destroyer of American communities" (p. 37); the GM streetcar conspiracy documented — National City Lines' bought-and-demolished electric systems in eighty-three cities by 1950, the antitrust convictions punished with "$1 (yes, one dollar) fines each" for executives (pp. 39–40), the anti-transit advertising ("WET DOG SMELL… CREEPS AND WEIRDOS," p. 40), and the PCC streetcar industry's extinction ("One is reminded of how China capriciously jettisoned its ships," p. 41); the Interstate Highway System as jobs program ("memories of the Great Depression were sufficiently fresh for everyone to recognize instantly the real and serious purpose of the program: full employment," p. 58); and the Washington Square closure re-tested at Toronto (pp. 73–74) and confirmed by the University College London study — "an average of 20% of the traffic it carried seems to vanish" (p. 75) — with the "traffic is like water" paradigm named as abandoned science (see scientific-state-of-mind). The 2004 book converts erosion's spatial analysis into the community pillar's destruction mechanism (see community-resources).

Source Support linking rule: All entries in this section must be wikilinks to source note pages in wiki/source-notes/ using the source-notes/ path prefix. Never link to raw files — raw files are not wiki pages.

This page requires fuller treatment — created at the Jacobs ingest; awaits the induced-demand and traffic-evaporation literatures that later confirmed the "vanished cars" finding, and the wiki's dromology register as the speed-theory counterpart.

Open Questions

• Jacobs's Washington Square case is the founding demonstration of what transport planning later called traffic evaporation. Does the wiki's evidence base (Morey & Alkanoglu's automobile vernacular; Soja's LA) describe erosion still winning, or has selective attrition — congestion pricing, bus lanes — become the operative policy at scale?
• Attrition is framed as an evolutionary, piecemeal strategy ("each change is absorbed piecemeal, as it occurs," p. 370). Is that gradualism a strength against political backlash, or does it cede the speed of the erosion process it competes with?