Never Besiege a City

The rule is not to besiege walled cities if it can possibly be avoided. The preparation of siege equipment takes three months, and the building of mounds against the walls takes another three months.

Some objectives are not worth their cost. A walled city — a fortified position, an entrenched competitor, a bureaucratic institution — can be taken, but the cost in time, resources, and morale may exceed any possible benefit. If you must besiege, do it only when there is no alternative.

Sun Tzu's warning against siege warfare is practical and vivid. He describes the general, unable to control their frustration, ordering troops to swarm the walls like ants, with a third of them killed and the city still untaken. A sharp psychological insight follows: siege warfare is often driven by frustration and ego rather than strategic calculation. The general who attacks walls is the general who has run out of ideas. The warning against siege follows a practical calculation: fortified cities consume months of labor, equipment, supplies, and lives. It is an argument about opportunity cost under wartime conditions, not a metaphor that every difficult person or institution must be bypassed. Some barriers require patient engagement, lawful challenge, or collective action. The useful question is whether the chosen route is proportionate to the goal and whether another route would preserve more people and resources. Persistence is not automatically courage when the strategy itself is unsound. The image of the wall can tempt a reader into a slogan about always finding an easy route. The text is more sober: some objectives are strategically possible but politically ruinous. Ask not only whether a barrier can be overcome, but whether overcoming it would leave anything worth keeping. A strategic retreat can preserve the possibility of a better settlement later A strategic retreat can preserve the possibility of a better settlement later.