Personally, I think this statement is true. All it takes is a group of people getting fed up enough with something for a revolution to happen. Looking back to some events in the past such as the revolutionary war, slavery, women's rights, etc... In each case, and many more, a group of people were upset about restraints on their freedoms and over time more people joined their cause. Until eventually they had a group powerful enough to cause something to change.
This statement to me means that even if there's a great injustice somewhere making it so that there is no liberty, that there eventually will be again. There is always at least one person with a spark in them that will eventually get so big, they'll ignite the flame once again. I think this statement is also trying to encourage everyone to be one of those people. Someone who won't put up with tyranny and sit back while someone is trying to take or violate their rights. An individual that will eventually fight back or cause a movement and even those that will later join into that movement.
I think this statement sums up what we are trying to learn from this class as well. We are learning about these kinds of people in history who were heroes establishing liberty. They were part of a movement. We also are learning how to recognize when there is an injustice happening and not to be vulnerable to propaganda. I now see how easily a nation can be indoctrinated into giving away or allowing their freedoms to be taken. This all has caused me to realize how truly priceless my freedoms are.