Historically things get really bad before they get better. A revolution is the most obvious sign of this tendency. The French revolution is often put forward as an example of poverty, need and desperation becoming so widespread that an overthrow of the Aristocratic, governing class was demanded.
A true revolution however, does not just overthrow the present system to install a similar one. A revolution implies that what was tried for generations has failed, and a new system with new checks and balances to power takes its place. The French revolution was inspiring because although far from perfect in application, values of brotherhood, equality and justice were demanded.
What drives any revolution is what Bob Dylan called the answer that is "Blowin' in the wind." It is the need for change. The American Revolution set aside the powers of king and priest, insisting upon rule of law, and citizenship participation, in their place. Minorities, women, and non humans would just have to wait for further revolutions for inclusion in improved systems of society.
A revolution does not always have to be bloody. In India the largest democracy on Earth emerged from Gandhi enlisting hundreds of thousands of people in practicing non violent insistence of self rule. Although there was certainly some bloodshed, and in the end Gandhi himself was assassinated, India emerged as an effective nation despite the very different languages, sects, traditions and differences throughout India.
Inspired by Gandhi, Martin Luther King in the United States of America, ignited a revolution when he insisted a person's character is more important than a person's color. He changed, revolutionized, the way in which oppressed peoples saw themselves. Part of not being victimized, he taught, is to assert dignity, strong character and unwavering determination for improvement. This could not have happened without the greater part of the nation's citizenry agreeing that justice and equality is for all, not just for a few.
A great cause in any revolution is that the moment is right for change. A non nationalistic example is that for two hundred years the whole world has become very dependent upon burning of fossil fuels to create every kind of energy. Clean, alternative energy is being developed world wide. The revolution at hand is the slow dying away of the old methods of extracting fuel from the earth and the new innovations and requirements to technology that will change entirely not just how people use energy, but how they view themselves. Creating a positive cooperation with living systems, rather than just exploiting and conquering them, displays a revolution in how people view their relationships to one another and to the larger, living world.
To learn from history, most people have realized that people do not much learn from history. Therefore, the struggles for any oppressed peoples, living systems, forests, planets and so on must be renewed with each lifetime. The revolution at hand with humanity at present, is the realization that people are sustained by internal and external living systems of which they are a part and which are a part of them.
The realization that cooperating with one another, protecting and appreciating life and avoiding destruction depends upon not just people seeing people as kin, but people seeing (in a revolutionary new sense), that science, biology and sustainable living is affected by eliminating exploitative relationships and reinforcing cooperative relationships for life.
In the present world, there is still an extremely powerful grip over most life on earth controlled by an elite, wealthy few. Getting money and corruption out of world governments will be difficult. But new systems for replacing exploitation with cooperation are already whispered on the wind.
When power and energy are infinite and abundance is protected as sacred; there will be no way for tyrants to control the populace. The problem of oppression by a few is as old as humanity, but the coming revolution that changes it is as new as can be. It is revolutionary, and will only arrive when things get so bad that a greater majority demands real change. And so it goes.