Why did it matter whether a territory joined the union as a free or slave state?

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What was the national government’s biggest concern if facing a war, under the articles of confederation? the national government had no national military. the country had grown too large to defend with a small army. the states would not back the federal government. there was no way the states would pay for fighting a war.

The chinese exclusion act was the first significant law restricting immigration into the united states. why do you think the us government singled out chinese immigrants in particular for exclusion?