LONDON (AP) — The world has entered an era of increasing instability as countries around the globe boost military spending in response to Russia’s invasion of Ukraine, the Hamas attack on Israel and China’s growing assertiveness in the South China Sea. That’s the conclusion of a new report Tuesday from the International Institute for Strategic Studies, which also highlighted rising tensions in the Arctic, North Korea’s pursuit of nuclear weapons and the rise of military regimes in the Sahel region of Africa as contributing to a “deteriorating security environment.” The London-based think tank has compiled its annual estimate of the global military situation for the past 65 years. “The current military-security situation heralds what is likely to be a more dangerous decade, characterized by the brazen application by some of military power to pursue claims — evoking a ‘might is right’ approach — as well as the desire among like-minded democracies for stronger bilateral and multilateral defense ties in response,’’ the report said.