Why does Roosevelt say that America should not assume that they have time to prepare and that the Atlantic Ocean will prevent an invasion?

To designate young isolationists, who deluded themselves into believing that America could remain aloof, secure, and distant from the wars raging in Europe, Roosevelt liked the amusing term "shrimps"-- crustaceans possessing a nerve cord but no brain. In that critical month of May 1940, he finally realized that it was probably a question of when, not if, the United States would be drawn into war. Talk about neutrality or noninvolvement was no longer seasonable as the unimaginable dangers he had barely glimpsed in 1936 erupted into what he termed a "hurricane of events."Explanation:

in the 1800s, locomotives powered by steam made transportation faster and cheaper. the resulting rapid growth of railroads led to the connection of the atlantic and pacific railroad in oklahoma city in 1897.

in the last years of the century, the improvement of steam-based engines the expansion and growth of railroads. this growth increased when the companies started to build and expand, such as the atlantic and pacific railroad, which connected new mexico with california, and missouri with oklahoma. many of these new networks were built in oklahoma, and these changes transportation henceforward.

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