There were many reasons. For starters, it involved getting rid of a large number of Native Americans, and while some supported this, others opposed it as they were peaceful. Another thing was that this meant the introduction of new states and it deepened the division based on whether the states should be slave states or non-slave states. Also they involved war with Mexico and some wanted this and some didn't.
        
             
        
        
        
Increased tensions between the countries and development of many dangerous weapons. 
        
             
        
        
        
A. Congress hoped i helped :)
        
                    
             
        
        
        
He requested a wagon or chariot (I believe).
        
             
        
        
        
Discipline problems often arose among the settlers.
Many settlers had a knowledge of wilderness survival.
Many died from diseases before reaching their destination.