[111] Polk's tenure saw continued technological improvements, including the continued expansion of railroads and increased use of the telegraph.[111] These improved communications encouraged a zest for expansionism.[112] However, sectional divisions became worse during his tenure.
Polk set four clearly defined goals for his administration:[112]

Reestablish the Independent Treasury System – the Whigs had abolished the one created under Van Buren.
Reduce tariffs.
Acquire some or all of the Oregon Country.
Acquire California and its harbors from Mexico.
While his domestic aims represented continuity with past Democratic policies, successful completion of Polk's foreign policy goals would represent the first major American territorial gains since the Adams–Onís Treaty of 1819.[112]

Transition, inauguration and appointments[edit]
Further information: Inauguration of James K. Polk
President Polk, BEP engraved portrait
Polk formed a geographically balanced Cabinet.[113] He consulted Jackson and one or two other close allies, and decided that the large states of New York, Pennsylvania and Virginia should have representation in the six-member Cabinet, as should his home state of Tennessee. At a time when an incoming president might retain some or all of his predecessor's department heads, Polk wanted an entirely fresh Cabinet, but this proved delicate. 