(a) two devastating world wars;

(b) the Great Depression of the 1930s;

(c) the end of vast colonial empires;

(d) rapid advances in science and technology, from the first airplane flight at Kitty Hawk, North Carolina (US) to the landing on the moon;

(e) the Cold War between the Western alliance and the Warsaw Pact nations;

(f) a sharp rise in living standards in North America, Europe, and Japan;

(g) increased concerns about the environment, including loss of forests, shortages of energy and water, the decline in biological diversity, and air pollution;

(h) the onset of the AIDS epidemic; and

(i) the ultimate emergence of the US as the only world superpower. The planet's population continues to explode: from 1 billion in 1820, to 2 billion in 1930, 3 billion in 1960, 4 billion in 1974, 5 billion in 1988, and 6 billion in 2000.

For the 21st century, the continued exponential growth in science and technology raises both hopes (e.g., advances in medicine) and fears (e.g., development of even more lethal weapons of war).

The surface of the earth is approximately 70.9% water and 29.1% land. The former portion is divided into large water bodies termed oceans. The World recognizes and describes five oceans, which are in decreasing order of size: the Pacific Ocean, Atlantic Ocean, Indian Ocean, Southern Ocean, and Arctic Ocean.

The land portion is generally divided into several, large, discrete landmasses termed continents. Depending on the convention used, the number of continents can vary from five to seven. The most common classification recognizes seven, which are (from largest to smallest): Asia, Africa, North America, South America, Antarctica, Europe, and Australia. Asia and Europe are sometimes lumped together into a Eurasian continent resulting in six continents. Alternatively, North and South America are sometimes grouped as simply the Americas, resulting in a continent total of six (or five, if the Eurasia designation is used).

North America is commonly understood to include the island of Greenland, the isles of the Caribbean, and to extend south all the way to the Isthmus of Panama. The easternmost extent of Europe is generally defined as being the Ural Mountains and the Ural River; on the southeast the Caspian Sea; and on the south the Caucasus Mountains, the Black Sea, and the Mediterranean. Africa's northeast extremity is frequently delimited at the Isthmus of Suez, but for geopolitical purposes, the Egyptian Sinai Peninsula is often included as part Africa. Asia usually incorporates all the islands of the Philippines, Malaysia, and Indonesia. The islands of the Pacific are often lumped with Australia into a "land mass" termed Oceania or Australasia.

Although the above groupings are the most common, different continental dispositions are recognized or taught in certain parts of the world, with some arrangements more heavily based on cultural spheres rather than physical geographic considerations.

Global output rose by 5.2% in 2007, led by China (11.4%), India (9.2%), and Russia (8.1%). The 14 other successor nations of the USSR and the other old Warsaw Pact nations again experienced widely divergent growth rates; the three Baltic nations continued as strong performers, in the 8%-10% range of growth.

From 2006 to 2007 growth rates slowed in all the major industrial countries except for the United Kingdom (3.1%). Analysts attribute the slowdown to uncertainties in the financial markets and lowered consumer confidence. Worldwide, nations varied widely in their growth results. Externally, the nation-state, as a bedrock economic-political institution, is steadily losing control over international flows of people, goods, funds, and technology. Internally, the central government often finds its control over resources slipping as separatist regional movements - typically based on ethnicity - gain momentum, e.g., in many of the successor states of the former Soviet Union, in the former Yugoslavia, in India, in Iraq, in Indonesia, and in Canada.

Externally, the central government is losing decision making powers to international bodies, notably the EU. In Western Europe, governments face the difficult political problem of channeling resources away from welfare programs in order to increase investment and strengthen incentives to seek employment. The addition of 80 million people each year to an already overcrowded globe is exacerbating the problems of pollution, desertification, underemployment, epidemics, and famine. Because of their own internal problems and priorities, the industrialized countries devote insufficient resources to deal effectively with the poorer areas of the world, which, at least from an economic point of view, are becoming further marginalized.

The introduction of the euro as the common currency of much of Western Europe in January 1999, while paving the way for an integrated economic powerhouse, poses economic risks because of varying levels of income and cultural and political differences among the participating nations.

The terrorist attacks on the US on 11 September 2001 accentuated a growing risk to global prosperity, illustrated, for example, by the reallocation of resources away from investment to anti-terrorist programs. The opening of war in March 2003 between a US-led coalition and Iraq added new uncertainties to global economic prospects. After the initial coalition victory, the complex political difficulties and the high economic cost of establishing domestic order in Iraq became major global problems that continued through 2007.

stretching over 250,000 km, the world's 322 international land boundaries separate 194 independent states and 70 dependencies, areas of special sovereignty, and other miscellaneous entities; ethnicity, culture, race, religion, and language have divided states into separate political entities as much as history, physical terrain, political fiat, or conquest, resulting in sometimes arbitrary and imposed boundaries; most maritime states have claimed limits that include territorial seas and exclusive economic zones; overlapping limits due to adjacent or opposite coasts create the potential for 430 bilateral maritime boundaries of which 209 have agreements that include contiguous and non-contiguous segments; boundary, borderland/resource, and territorial disputes vary in intensity from managed or dormant to violent or militarized; undemarcated, indefinite, porous, and unmanaged boundaries tend to encourage illegal cross-border activities, uncontrolled migration, and confrontation; territorial disputes may evolve from historical and/or cultural claims, or they may be brought on by resource competition; ethnic and cultural clashes continue to be responsible for much of the territorial fragmentation and internal displacement of the estimated 6.6 million people and cross-border displacements of 8.6 million refugees around the world as of early 2006; just over one million refugees were repatriated in the same period; other sources of contention include access to water and mineral (especially hydrocarbon) resources, fisheries, and arable land; armed conflict prevails not so much between the uniformed armed forces of independent states as between stateless armed entities that detract from the sustenance and welfare of local populations, leaving the community of nations to cope with resultant refugees, hunger, disease, impoverishment, and environmental degradation

The United Nations High Commissioner for Refugees (UNHCR) estimated that in December 2006 there was a global population of 8.8 million registered refugees and as many as 24.5 million IDPs in more than 50 countries; the actual global population of refugees is probably closer to 10 million given the estimated 1.5 million Iraqi refugees displaced throughout the Middle East (2007)

Current situation: approximately 800,000 people, mostly women and children, are trafficked annually across national borders, not including millions trafficked within their own countries; at least 80% of the victims are female and up to 50% are minors; 75% of all victims are trafficked into commercial sexual exploitation; almost two-thirds of the global victims are trafficked intra-regionally within East Asia and the Pacific (260,000 to 280,000 people) and Europe and Eurasia (170,000 to 210,000 people)

Tier 2 Watch List: Albania, Argentina, Armenia, Azerbaijan, Bahrain, Burundi, Cameroon, Central African Republic, Chad, China, Costa Rica, Cote d'Ivoire, Cyprus, Democratic Republic of the Congo, Dominican Republic, Egypt, Equatorial Guinea, Gabon, The Gambia, Guatemala, Guinea, Guinea-Bissau, Guyana, India, Jordan, Libya, Malaysia, Montenegro, Mozambique, Niger, Panama, Republic of the Congo, Russia, South Africa, Sri Lanka, Tajikistan, Uzbekistan, Venezuela, Zambia, Zimbabwe

Tier 3: Algeria, Burma, Cuba, Fiji, Iran, Kuwait, Moldova, North Korea, Oman, Papua New Guinea, Qatar, Saudi Arabia, Sudan, Syria (2008)

cocaine: worldwide coca leaf cultivation in 2005 amounted to 208,500 hectares; Colombia produced slightly more than two-thirds of the worldwide crop, followed by Peru and Bolivia; potential pure cocaine production rose to 900 from 645 metric tons in 2005 - partially due to improved methodologies used to calculate levels of production; Colombia conducts aggressive coca eradication campaign, but both Peruvian and Bolivian Governments are hesitant to eradicate coca in key growing areas; 551 metric tons of export-quality cocaine (85% pure) is documented to have been seized or destroyed in 2005; US consumption of export quality cocaine is estimated to have been in excess of 380 metric tons

opiates: worldwide illicit opium poppy cultivation reached 208,500 hectares in 2005; potential opium production of 4,990 metric tons was only a 9% decrease over 2004's highest total recorded since estimates began in mid-1980s; Afghanistan is world's primary opium producer, accounting for 90% of the global supply; Southeast Asia - responsible for 9% of global opium - saw marginal increases in production; Latin America produced 1% of global opium, but most was refined into heroin destined for the US market; if all potential opium was processed into pure heroin, the potential global production would be 577 metric tons of heroin in 2005