That right there should have been a big warning sign that the whole plan was to turn the U.S. from a sovereign nation into a globalist empire. If you “acquire” a foreign land without turning it into new U.S. states, then tariffs in the U.S. completely undermine you.
The whole purpose of “acquiring” these foreign lands was to replace the cheap sources of labor that previously existed in the U.S. but was disappearing through the abolition of slavery and the introduction of labor laws here.
The United States didn’t really become a sea power until Teddy Roosevelt launched the Great White Fleet in 1907. These were built after the Spanish-American War.
And while these were modern steel warships they were obsolete as soon as they were launched. Britain’s 1906 HMS Dreadnought had changed everything.
One factor leading to America seeking to be a global seapower was Alfred Thayer Mahan’s 1890 book “The Influence of Sea Power upon History”. This book had a worldwide impact, all of the major powers adopted its lessons. Mahan was the president of the US Naval War College. Teddy Roosevelt corresponded with Mahan about his theories before the Spanish American War.
There’s another work on strategic theory written around that time that has continued to have influence ever since, Halford Mackinder’s “The Geographical Pivot of History”.