There is no better option in this question
This is because the main reason that led to the rise of nativism in the 1920's was the increase of immigrants into the USA. The most feared of these immigrants were the German.
The Democratic Republic of the Congo :)
The issue of whether to permit slavery in the territories organized in this new land consumed Congress at the end of the 1840s. During the war, Congressman David Wilmot introduced the Wilmot Proviso, a proposal to ban slavery in any new territory acquired from Mexico. The measure passed in the House of Representatives but failed in the Senate.
Congress was also seeking resolutions for several other controversial matters. Antislavery advocates wanted to end the slave trade in the District of Columbia, while proslavery advocates aimed to strengthen fugitive slave laws. But the most pressing problem was California: the many emigrants who had flocked to the territory upon the discovery of gold in the late 1840s had forced the question of its statehood and status as a slave or free state.
The presidential election of 1848 determined which of these issues would be tackled first.
There would be Major conflict at first but as I understand it would be resolved
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