For a pair of great powers that have long-held pacifist policies, Russia's invasion of Ukraine appears to have flipped the calculus.

Germany’s stunning announcement that it would massively boost its defense budgets — a historic policy shift triggered by the war in Eastern Europe — is widely expected to impact Japan’s own spending as calls grow for a similar move by Tokyo.

The unexpected and dramatic rethink by Germany comes as leaders in Japan debate doubling the country’s defense budget to 2% of gross domestic product from an informal cap of around 1%.