Geographic feasibility. Many experts have considered the US impossible to invade because of its major industries, reliable and fast supply lines, large geographical size, geographic location, population size, and difficult regional features.

Is the United States the hardest country to invade?

#1: United States

The United States is by far the hardest nation to invade. Setting aside their population of over 325 million people, many of whom take the second amendment quite seriously, and the country's varied, often merciless terrain, their biggest advantage is a financial one.

Can war happen on US soil?

The Battle of Attu was the only land battle to be fought on North American soil during World War II. + Add to calendar. The Battle of Attu was the only land battle to be fought on North American soil during World War II.