“The civil constitution of every state shall be republican.”Immanuel Kant · Spre pacea eternă · 1795 · Articolul definitiv 1
Those who decide on war must also bear its costs, or they wage it lightly.
Republican here means not direct democracy but a system where citizens are simultaneously legislators and subjects of the laws they make, with executive power separated from the legislative. The mechanism: those who decide on war also bear its costs, so they hesitate to start one; a monarch who pays no such price can wage war lightly. Kant saw in this structure the basic condition of peace among states.
Kant adds a rarely noticed nuance: republicanism is not about who votes, but about who answers for decisions. He separates the republican from the democratic, which he even sees as dangerous — a crowd can decide directly, but without mechanisms to restrain it. An apartment building decides, through representatives, on roof repairs; if the decision is made by all neighbors gathered in the stairwell, without clear rules, some will block, others will impose. Structure matters more than the number of voters. From here comes the next question: what guarantees that representatives actually bear the costs of their decisions?
Why it matters The idea underlies democratic peace theory and the critique of governments that decide wars their citizens alone pay for in blood and money.