What are two events that preserve the union and one that tear it apart?

Historians and political scientists use the phrase Second Party System as a term of periodization to designate the political party system operating in the United States from about 1828 to 1854, after the First Party System ended. The system was characterized by rapidly rising levels of voter interest, beginning in 1828, as demonstrated by Election Day turnouts, rallies, partisan newspapers, and high degrees of personal loyalty to parties.

Two major parties dominated the political landscape: the Democratic Party, led by Andrew Jackson, and the Whig Party, assembled by Henry Clay from the National Republicans and from other opponents of Jackson. Minor parties included the Anti-Masonic Party, an important innovator from 1827 to 1834; the abolitionist Liberty Party in 1840; and the anti-slavery Free Soil Party in 1848 and 1852. The Second Party System reflected and shaped the political, social, economic and cultural currents of the Jacksonian Era, until succeeded by the Third Party System. Towers specifies an important ideological divide:

d.prevent the spread of communism outside of eastern europe.

is there options? or is it random words?

explanation: