President Obama recently proclaimed that climate change, more than any issue, will define the contours of the 21st century. Powerful men searching for legacy often evoke grand challenges and personal solutions, but climate change is only one of several forces that will make civilization different 100 years from now.

1. Challenges to Democracy

In the 19th and 20th centuries, democracies embracing free markets outperformed more autocratic and collectivist societies. However, over the last several decades, majority rule in the West has fashioned government policies that redistribute income indiscriminately, displace investments in infrastructure and technology, and slow growth.

China – albeit with shortcomings – has created a neocapitalist juggernaut. Its Communist Party is not Soviet-era dictatorship but rather an oligarchy open to new members. It imposes guidance on private, as well as state-owned, enterprises, and it has avoided the worst impulses of prosperity – a sense of entitlement and complacency among citizens.

China and oligarchy will triumph if Western democracies don’t curb politicians’ impulse to reward indolence, much as Roman emperors did with free bread and circuses.

2. Global Migration

In advanced industrialized economies, declining birth rates compel reliance on foreign workers and immigration. Often, ethnicity defines the national character that made those societies successful, and many new arrivals bring ideas and expectations about government that caused their homelands to fail.

Advanced societies lack adequate mechanisms for assimilating newcomers and are clumsy at imparting national values – consider the backlash against immigrants in Norway, or how effectively ISIS recruits in Europe.

Ultimately, politicians’ impulse to placate whoever has a vote, regardless of long-term consequences, poses another threat to the preservation of democratic capitalism.

3. Wedding Machines to Humans

Handheld computers and the Internet give each person real-time access to vast knowledge and global communications, and an eerie intimacy with omnipresent devices that chronicle their lives.

Robots perform many tasks better than humans, but no artificial intelligence will ever replace the human mind, because computers are only as good as what we put into them. However, within a few decades, tiny chips and processors placed inside human brains will be commonplace. By mere concentration, we will be online and accomplish accelerated computer-assisted access to information, problem solving and communication.

Wedded to machines, we all may become brilliant, but any pretense of privacy may be lost.

4. Customized Human Beings

Bioethicist Ezekiel Emanuel has written that he hopes to die at 75 because as humans age, mental and physical capacities decline and old folks inevitably burden the young. He has delineated medical care he will forgo after that age, but such prescriptions are unlikely to be generally embraced.

Still, humans are living longer, and society can’t afford to retire people in their 60s and pay pensions into their 90s. Computer implants will permit repair and customized enhancement of the brain, extend work into our late 70s and make life more productive and rewarding longer.

Breakthroughs in DNA and stem cell research will make organ replacement and enhancement routine. A more durable and intelligent human race will be reality, not science fiction.

5. Climate Change

Humans are unique among species in their ability to adapt to and to change their environment. They have been doing so since the Ice Age to cope with natural climate cycles.

Local populations fell to extinction or conquest if they failed to cope. Now humanity must act as one to address rising atmospheric temperatures. Otherwise, individual societies will be forced to mitigate the consequences, and the Darwinian cycle among competing cultures will continue.

As influential as that challenge may be, reinventing democracy and re-engineering the human species are likely to be as big.

It takes a lot of hubris to say you can see the world a century from now – this writer included.

Peter Morici served as Chief Economist at the U.S. International Trade Commission from 1993 to 1995. He is an economist and professor at the Smith School of Business, University of Maryland, and a widely published columnist. He is the five time winner of the MarketWatch best forecaster award. Follow him on Twitter @PMorici1.