No one can be happier than Shinzo Abe that Sunday’s upper house election tipped the legislative balance in favour of lawmakers open to revising Japan’s constitution. But throwing off the constraints that followed military defeat and occupation, long an ambition of the prime minister, will be far less important than building a firm foundation for the nation’s future.

A growing number of Japanese people seem taken with the notion that they should try crafting their own constitution. The 100 or so articles of the 1947 document, drafted under occupation by the Allied powers, offset the power of the prewar state by strengthening the individual rights that support popular sovereignty. They protect the choices — of religion, work, protest, due process — Japanese citizens today take for granted.

As tensions intensify across Asia — in the South China Sea, for example — the focus is largely on Article 9, the “no war” clause. Japan’s military decisions are increasingly shaped by its neighbours’ rising capabilities. North Korea’s pursuit of nuclear weapons prompted Tokyo to invest heavily in ballistic missile defence. China’s growing maritime reach has drawn attention to Japan’s readiness to defend its waters and its islands. Last year Mr Abe’s cabinet reinterpreted the constitution to allow the military to co-operate with others, primarily the US, if its own security is threatened.