Well written was the letter of March 7 titled “Power grid story should open eyes.” I would add an extra-large portion or ingredient of vulnerability. History teaches the United States to be vigilant. Should there have been more vigilance pre-Pearl Harbor? Before Sept. 11, 2001? Before balloons travel over our nation? I am all in favor of diversity in our energy and power sources, and in favor of what-ifs. What if rogue solar flares take out our electrical grid? Or foreign adversaries? Or breakdown of supply chain resources? Reliable energy sources such as fossil fuels, along with alternative choices, must continue to provide our power for many years, whether for vehicles or the grid. The United States’ citizens deserve to be prepared. Healthy brainstorming dialogues and vigilance should bring a dose of wisdom to this ongoing history lesson.