The Treaty of 1783 resulted in Britain still having some influence in continental North America. This influence would continue into the 19th century, as Britain occupied modern day Oregon up until the 1840's.
At the end of the Revolution, this border was agreed upon for several different reasons.
1) This would ensure that Britain has no political or economic control over any of the 13 original colonies.
2) It would avoid fighting over land that technically belongs to different Native American tribes.
The quote that most clearly reflects pressure from superiors as motivation for bias in media is “Robbins doesn’t have a shot at winning and isn’t worth covering, but my editor says we have to make him look electable.”