Why did some in the northwest and some antislavery forces call the agreement a "base betrayal by the south"

James Knox Polk, also called "Young Hickory" won the presidential election of 1844 with the combination of southern and western expansionism ideas. Dealing with a war with Mexico about the annexation of Texas and having to settle a treaty with the British empire over Oregon, they rapidly accepted what the UK had to offer. They submitter a drafty treaty extended the border between US and Canada along the 49th parallel. The treaty was ratified 3 days after.

As a result, a group of northwester expansionists, unsatisfied with the treaty, saying they cared more about annexing entire Texas but not entire Oregon, joined antislavery forces and condemned what they regarded a base betrayal by the South.

east-west schism. the greatest effect of the east-west schism was the creation of two separate churches that had previously been unified under one church, the eastern orthodox church and the roman catholic church.

the underground railroad (apocope of the metropolitan railroad) is a system of urban trains located within a city and its metropolitan area. it is characterized for being a massive transport of passengers in the big cities, uniting diverse zones and their environs, with high capacity and frequency and in segregated form to other systems of transport. metropolitan railroads are built underground or on the surface, although most systems use mixed models where sections are combined in both modalities.

1 - as a result, the metro tends to reduce car travel for two reasons: first, due to the greater transfer of users from the car and, second, due to the reduction in the acquisition of cars in homes located in sectors near the stations of the metro.

2 -the metro allows to contribute effectively to the achievement of all the objectives of an urban development policy: it improves the efficiency of the city's economy by reducing travel costs and also generates a higher level of activities in the city center, taking advantage of of the agglomeration economies.

3 -it is a clean means of transport, since it uses renewable energy (usually electricity), taking care of the environment and avoiding excessive pollution.