Why Is American English Spelling So Complicated Complex Weird?

Simply speaking - because it has been influenced by so many different languages.

You probably know that another word used for English is Anglo-Saxon.  Did you know, though, that the “Anglos” and the “Saxons” were two out of three German(ic) tribes or people, which (or that or who) moved to Britain from current day Germany and Denmark?

 

The legend has it, and according to historians it’s not just a fairy-tale, that at first they were invited by the King to help the native Britons, who spoke Brittonic languages (modern Welsh), fight off the neighbors after the Romans had left.

American English Spelling vs. Pronunciation

Spelling versus (vs.) pronunciation or writing and reading.

Every language has rules, which, from the perspective of a foreign language student, make it easier to learn.  The principle followed here is association.  You know one thing, you see something else like it, you think it works in exactly the same or a similar way.  There is even an old English proverb for that. 
 “Like father like son”.  This truth is so universal that you can probably find an equivalent saying in most if not all languages.