If you had read a little further into the history of the modern world - or maybe spent a bit more time in a combat arm - you would have seen that our interests include any tactically/strategic part of the world that affects our ability to fight to protect ourselves from enemy domination (and slaughter).
Such as Sea Lanes of Communication (SLOCs), sources of strategic minerals (necessary for manufacturing modern alloys for weapons and engines), and sea control. The Chinese have figured all of this out and are rapidly gaining control of the sea and land routes to conduct and resupply warfare through their "Belts and Roads Initiative".
Vietnam was fought in part to prevent an earlier attempt by the communist powers to control the seaways around Vietnam (look up "Straits of Malacca") which would have caused our allies in the region to lose their ability be supplied in event of war. Looking at the position of Taiwan on a map should show you how important its position is for the continued survival of Japan and the Philippines.
Now, if you somehow served in uniform without realizing any of this, it is disappointing.
So you’re saying the Constitution is ineffective for global conflucts? Trump managed to keep enemies down while upholding the Constitution simultaneously.
That does not really matter as much as you might suppose.
The essential purpose of the Constitution was to limit and restrain the powers of government. That purpose remains valid without regards to available technology then or now.
And the Constitution has failed that purpose.
More specifically, the people of this country have failed to maintain the limits and restraints on government power that were imposed by the structure of the Constitution. There is too much loot to be obtained by running bigger and more powerful government as an unstoppable engine of theft. Political arguments degenerate essentially into who gets to control the engine.
The founders were certainly wrong about the utility of State militias verses a regular standing army. Armies always beat militias unless the "militias" are solidly backed by foreign powers and military advisors.
The founders certainly never conceived of an American nation that would be a world power that maintained and required control of strategic trade resources in far-away places. Perhaps it was that success that has doomed the Constitutional purpose of restraining government power.
So what comes next? The story is "to be continued".