Kerry warns that energy has already been weaponized against Europe twice in four years and says the continent won't get unlimited winters to learn the lesson. Europe has weathered three energy crises in four years, from Russia's invasion of Ukraine to the ongoing Strait of Hormuz blockage, and gas reserves now sit near just 50 percent capacity. A failure to fully acknowledge the extent of Europe’s energy insecurities could lead to national security vulnerabilities, according to former United States Secretary of State John Kerry. “Over the past four years, the price of energy has done more damage to Europe than any kinetic weapon,” Kerry writes. Energy has been used as a weapon against Europe twice in four years, and it will be again,” Kerry warns.