And most of those founding fathers were there when the US Navy was established to protect our trade and coasts, and agreed to it. As well as the Marine Corps, our first "expeditionary" capability derived from the Navy.
We had an advantage - we weren't in Europe surrounded by a bunch of historically hostile Powers. We had Canada to the north, with negligible offensive capability, and to the south and west were bordered by natives and weak colonies. A standing army wasn't needed. By 1812, we had one and we'd keep it forever - we realized the limitations of the "well-regulated militia" Teancum refers to.
It wasn't that long ago we had three powers openly espousing their intention to dominate their neighbors, and then the world - Germany, Japan, and the USSR. WWII reduced the open militarism of the first two, and the following decades of Cold War, however expensive and bloody in proxy fights, didn't not result in global domination by the USSR (or, by the USA, which has NEVER espoused a mission to dominate our neighbors, Monroe Doctrine notwhithstanding). We're not that far from military brutalism in the world today - just look at Sudan. The armies of the so-called Western powers exist mostly to defend themselves by deterring others from frontal warfare, and are succeeding, as shown by the fact that terrorism is the weapon of choice by hostile parties, instead of frontal warfare.