Here is how fast America is changing: By the time today’s teenagers hit their 30s, there will be — for the first time ever — more minorities than whites, more old people than children, and more people practicing Islam than Judaism.

The big picture: The slow demographic shifts we've watched over decades will finally reach a tipping point in the 2040s. They'll transform what America looks like, where we live and what we fear.

What we will look like

We'll be older and less white in the 2040s.

Only 45% of 30-year-olds will be non-Hispanic whites in 2040. And minorities will become the majority in the U.S. by 2045, according to Census projections.

in 2040. And minorities will become the majority in the U.S. by 2045, according to Census projections. There will be more old people than children for the first time because of the falling fertility rates, the Census data shows . More than 1 in 5 Americans will be over the age of 65, putting a new level of stress on the nation's Social Security and health care systems.

than children for the first time because of the falling fertility rates, the Census data shows More than 1 in 5 Americans will be over the age of 65, putting a new level of stress on the nation's Social Security and health care systems. Immigrants will make up a record-breaking share of the population and will have a crucial role in carrying the economic load created by the elderly Boomers and Gen X-ers.

Why it matters: The white evangelical and non-college male voters who helped propel Donald Trump to the presidency will likely be losing their power. But having minorities in the majority doesn’t necessarily mean racial discrimination and inequality embedded in laws, society and power structures will disappear. That's going to be an ongoing conversation, and an increasingly urgent one.

What we will believe

Islam will have surpassed Judaism as the second most popular religion in the U.S. by 2040, according to the Pew-Templeton Global Religious Futures project. The majority share of Christians will be falling.

Nearly 1 in 4 Americans will be unaffiliated with religion, including 30% of 30-to-44 year olds. In 2010, just 18% of the same age group was unaffiliated.

will be unaffiliated with religion, including 30% of 30-to-44 year olds. In 2010, just 18% of the same age group was unaffiliated. Globally, there will be just as many 30-to-44 year old Muslims as Christians of the same age.

Where we will live

The vast majority of the U.S. population (87%) will live in urban areas, according to UN projections. The nation's cities will likely continue to accumulate all the power, technology and wealth, while rural areas fall behind.

will live in urban areas, according to UN projections. The nation's cities will likely continue to accumulate all the power, technology and wealth, while rural areas fall behind. Think about this: Just 20 years ago, less than half the world lived in urban areas, but in another 20 years close to two-thirds of the world population will live in cities.

What we will fear

30 year-olds and almost half of Americans in 2040 will have been born after the 9/11 terrorist attacks on the World Trade Center, but the young adults of the future will remember Parkland, Las Vegas and Orlando.

In place of foreign terrorist attacks, publicized acts of domestic terrorism will be ingrained in young adults' memory.

publicized acts of domestic terrorism will be ingrained in young adults' memory. Most veterans from the Vietnam era or before will be gone, according to the VA, but Russia's cyber tampering in U.S. and global elections will be clearly remembered.

or before will be gone, according to the VA, but Russia's cyber tampering in U.S. and global elections will be clearly remembered. Global average sea levels will be up to a foot higher than today, and the global average surface temperature will be near the 2-degree Celsius (3.6F) guardrail set by the Paris Climate Agreement.

will be up to a foot higher than today, and the global average surface temperature will be near the 2-degree Celsius (3.6F) guardrail set by the Paris Climate Agreement. According to multiple studies, summer sea ice may completely disappear from the Arctic by 2040.

summer sea ice may completely disappear from the Arctic by 2040. Technology and human behavior will be even more intertwined: 70% of relationships could begin online via companies collecting troves of personal data, according to research by eHarmony. And our brains might be uploaded to the internet, if Elon Musk gets his way.

will be even more intertwined: 70% of relationships could begin online via companies collecting troves of personal data, according to research by eHarmony. And our brains might be uploaded to the internet, if Elon Musk gets his way. Today, members of Congress struggle to grasp how Facebook works. In the future, they'll be faced with even more complex regulatory and ethical problems in a world of artificial intelligence, advanced genetic modification technology and automated vehicles.

In 2040, 30-year-olds along with 40% of the U.S. population will have been born after the iPhone was introduced, according to Census projections. Their entire lives will be documented by social media, which has been linked to the currently skyrocketing rates of anxiety, depression and suicide.

What we will accomplish

But we will also be wealthier and healthier than ever.

By 2040, both China and India will have long surpassed the U.S.'s overall GDP, according to OECD data. But GDP per capita will still be higher in the U.S. — at around $86K, up from $63K today, according to long-term projected growth rates and Census population projections.

will have long surpassed the U.S.'s overall GDP, according to OECD data. But GDP per capita will still be higher in the U.S. — at around $86K, up from $63K today, according to long-term projected growth rates and Census population projections. An American child born in the U.S. will be expected to live to 83 years old, according to UN projections — 5 years longer than today's life expectancy at birth.

born in the U.S. will be expected to live to 83 years old, according to UN projections — 5 years longer than today's life expectancy at birth. Only 3 of every 1,000 American births are projected to end in infant death — half the most recent rate, according to the UN.

are projected to end in infant death — half the most recent rate, according to the UN. The fertility rate will stabilize, and if current trends continue, the youth of 2040 will be more educated than ever.

The bottom line: Projections are never perfect. An event like the internet or 9/11 in the next several years could completely uproot the future we see. But it's already clear that the current rate of human advancement is turning the world we know upside down.

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