Prime Minister Vladimir Putin has warned that Russia's falling population poses a dire threat to the country's existence, which he will reverse with sweeping new social policies if he's elected to a third presidential term in polls that are now less than three weeks off.

In the fourth in a series of wordy programmatic articles aimed at spelling out what he would do with a fresh six-year Kremlin term, Mr. Putin said Monday that Russia's long-standing demographic crisis, which features low birth rates coupled with unusually high working-age male mortality, could eventually turn the huge country into "a geopolitical 'void' whose fate would be decided by other powers" unless current trends are turned around.

Among the measures he proposes are a fresh assault on Russia's catastrophic rates of male alcoholism, special allowances for women who have more than two children (an idea that's been tried before with limited success), improved housing and educational prospects for all Russians, and a "smart" immigration policy that will entice Russians living abroad to return to the motherland and attract educated and talented young foreigners.

When he first came to power 12 years ago, Putin inherited a catastrophic population crisis. The number of Russians was shrinking by 0.5 percent each year and the prospect of a national breakdown was widely discussed by social scientists. But a decade of relative political stability, higher living standards, and public health campaigns have boosted male life expectancy from a 2003 low of 58 years to 63 today, and raised fertility rates from about 1.2 children-per-woman in 2002 to 1.6 in 2011 (still short of the 2.1 level experts say is needed to sustain a population), according to the state statistics service Rosstat.

Nevertheless, Putin writes, "if existing trends continue," Russia's present population of about 143 million will plunge to about 107 million people by 2050 – a disaster for a country that occupies such a vast territory and contains around 40 percent of the world's natural resources and an extraordinary population loss in peacetime.

"But if we manage to formulate and implement an efficient, comprehensive policy for population saving, then Russia’s population may increase up to 154 million," he writes. "The historic cost at stake in choosing between action and inertia is therefore some 50 million lives within the next 40 years."

But what say demographic experts?

Russian demographic experts agree that their science is a tricky one, and that implementing sensible policies today can radically change population projections over several decades. Yet most say Putin's ideas are unlikely to make much of a dent in Russia's stubborn demographic decline, and will do nothing to change the internal migration that's hollowing out Russia's vast Siberian and far eastern territories, which contain most of the country's precious raw materials.

"Putin counts on lowering the mortality rate by reducing alcohol consumption and drug abuse and getting people to go in more for sports. These are realistic measures," says Boris Denisov, a demographer at Moscow State University. "But the authorities' wish to raise the birth rate is based on the idea that women and families want more children, but lack enough money and other resources to do so. So, the reasoning goes, if they are given apartments and more money, they will have more babies. There is no evidence to support this idea. Many countries in the world have higher living standards than Russia but the same or even lower fertility rates."

According to Putin, families with more than three children would receive housing priorities and a special allowance of 7,000 rubles (about $250) per child monthly, while other state benefits would make it easier for working women to find daycare, adjust their working schedules to maternal demands, and upgrade their professional qualifications.

"Many families with three children are living in poverty and, while you can't actually feed a child with 7,000 rubles a month, it's better than nothing," says Zhanna Zaynchkovskaya, an expert with the independent Center for Migration Studies in Moscow.