Why doesn't the international date line isn't in a straight line

If it was a straight line there would be issues with dates with some nations that are near the line. Imagine walking a 100 feet and being in a zone that had a different date, without even switching the country.

It is the doctrine that the us had the right and duty to expand throughout north america. it just means they believed they had the right to expand westward and they did! they stated with the 13 colonies and then they kept moving gaining different territories throughout the years