It cannot have escaped those who have attended with candor to the arguments employed against the extensive powers of the government, that the authors of them have very little considered how far these powers were necessary means of attaining a necessary end. They have chosen rather to dwell on the inconveniences which must be unavoidably blended with all political advantages; and on the possible abuses which must be incident to every power or trust, of which a beneficial use can be made. This method of handling the subject cannot impose on the good sense of the people of America. It may display the subtlety of the writer; it may open a boundless field for rhetoric and declamation; it may inflame the passions of the unthinking, and may confirm the prejudices of the misthinking: but cool and candid people will at once reflect, that the purest of human blessings must have a portion of alloy in them; that the choice must always be made, if not of the lesser evil, at least of the GREATER, not the PERFECT, good; and that in every political institution, a power to advance the public happiness involves a discretion which may be misapplied and abused. They will see, therefore, that in all cases where power is to be conferred, the point first to be decided is, whether such a power be necessary to the public good; as the next will be, in case of an affirmative decision, to guard as effectually as possible against a perversion of the power to the public detriment.
from Federalist # 41, by James Madison