Currently? probably overpopulation
Actually, the categories what are included as the exclusive powers of the Federal Government include those that are expressed or enumerated, implied power, and inherent power, except for RESERVED POWER. This is the kind of power which is the opposite of expressed power. Hope this answer helps.
<span>Its spread was limited by the Mediterranean Sea.
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<span>Lincoln believed that some politicians that lived northern were trying to stop slavocracy and his enemy Senator Steven Douglas was there for effort.</span>