Before the Virginia Ratifying Constitutional Convention, James Madison (1788) explained that "There are more instances of the abridgment of the freedom of the people by gradual and silent encroachments of those in power than by violent and sudden usurpations."
In other words, our liberties are most likely to be slowly eroded than taken by a bold, dramatic action. The small, incremental steps are generally easily disguised as simply a slight modification, a minor change, and general meets little or no resistance. But in retrospect, dozens of "minor changes" amount to dramatic infringements of our liberties.
This is why we must be ever vigilant, because those in power (of whatever political persuasion) are much more likely to slowly chip away at our freedom than to make a huge power grab. This is why every action of government should be viewed and critiqued in light of our First Principles of the rule of law, equality, the Social Compact, unalienable rights, and limited government. We must hold the line now, or the line will be slowly erased, and we will cease to be America.