When German foreign secretary Arthur Zimmermann, in a notorious 1917 telegram, offered the government of Mexico all sorts of rewards for attacking the southwestern United States and thereby sidetracking American support for the allies on the Western Front, Mexico balked. But its reason for backing off was not that it liked Americans or thought a preemptive attack would be unfair. Rather, President Carranza worried that Mexico lacked the military clout to take American territory. And even if it could have grabbed, say, Texas, Mexico did not have the power to control it — given a rowdy and armed English-speaking state population, one that Carranza worried was “better supplied with arms than most populations.” In other words, the Second Amendment and a frontier attitude helped to deter Mexico from taking up Zimmermann’s offer.
Isoroku Yamamoto (4 April 1884 – 18 April 1943), Fleet Admiral and Commander-in-Chief of the Imperial Japanese Navy during World War II: “You cannot invade the mainland United States. There would be a rifle behind every blade of grass.” This quote is from the files of the late Gordon W. Prange, chief historian on the staff of Gen. Douglas MacArthur and author of At Dawn We Slept (1981). Brooks Jackson at factcheck.org claims it’s a bogus quote.
We now know that FDR’s fears of a Japanese invasion of the West Coast were unfounded and that Japan never had such a plan. We also know that this quote is favored by advocates of the Second Amendment and that enemies of the Second Amendment have an incentive to declare it bogus. We also know that Yamamoto cautioned against war with the United States and that after Pearl Harbor he said he feared that Japan had “awakened a sleeping giant.”
Evan Thomas, in his book Sea of Thunder, makes clear that Yamamoto considered war with the United States to be reckless because the United States would never stop fighting. We therefore know enough about Yamamoto to make it at least plausible that the quote is accurate even though an exact cite for its origin has never been found.
Deterrence is having the power and the means to defend yourself and having it known by potential attackers that if you are attacked you have the will to use it. Effective deterrence means you probably won’t ever have to resort to violence. Thus, the Second Amendment is deterrence and deterrence is the foundation of peace.