Answer:
Shay's rebellion convinced American leaders that little protected them from anarcy
China was itself an established empire and could not be conquered the same way as they did Africa and India.
What you are saying is basically equal to saying why not land in England (during that period) and turn everyone into slaves.
Since that is impossible, establishing spheres of influence allows major powers to break China from the inside.
The major powers of europe, Japan, and America ganging up on china during those days is the main reason behind China's firm foreign policy today.
<span>Industrialized countries around the world built canals during 19
century in order to have quick and less hustle transport of goods and products.
To have a progressive economy, products have to be transported swiftly from
where it made to everywhere it needs, to maintain the quality of
the products.</span>
