Immigration issues occupy the center stage at regional, national, and international level. It is not a new phenomenon, in fact is as old as humanity itself. It has become increasingly a key feature of the Liberalization, Privatization and Globalization [LPG] since the 1990s, and a major part of everyday life in various countries. Over the last 35 years, the number of persons living outside their country of birth has more than doubled to stand today at over 175 million people. Worldwide, approximately, one out of every 35 persons is an immigrant.

Immigration is defined as a temporary or permanent change of residence of an individual. It is a sub-category of a more general concept of 'movement', which embraces a wide variety of forms and types of geographical mobility. LPG policies have brought together nations, at the same time distanced them as well. Day by day, the impact of immigration has been increasing because of several factors operating in the society such as, and its social culture, the world economy, policies and procedures. Immigration is affecting the national security, public safety and particularly immigration laws in developed and developing countries.

Poverty, wars, famine and repression are among the major causes for immigration; but individuals quote other reasons like population pressures and insufficient resources, wage inequalities between countries, growing urbanization, rapid technological changes, migrant networks that facilitate movement, lack of employment prospects and debt in their own countries, and flexible labor market policies, rules and regulations are the major forces, which cause for massive immigration in the United States.

More number of people decide to make the United States of America as their home for different reasons. It is known as the land of immigration. It has been a nation of immigrants for 200 years. Generally, the people who migrate to US belong to developing countries. Political, religious, economic, military and legal factors have played a significant role in America's immigration history. The development of the American immigration legal system began after the American Civil War. It can be seen that immigration has evolved into something that has a dynamic impact on the economy. It is also something that has greatly affected the US laws.

Geographical-wise immigrants are highly concentrated in US. Mostly, they settle in the central part of Metropolitan Areas "gateway [major international airport] cities", due to high concentration of immigrants in six states such as California, New York, Texas, Florida, New Jersey and Illinois.

Immigrants in the "Before 1970" cohort are mostly referred to as Europe (39 percent), the British Isles (8 percent), Canada (9 percent) and Mexico (13 percent). The 1970s and 1980s and 1990s saw a rise in the importance of Asia, Mexico and South and Central America as immigrant source regions, and a decrease in the relative importance of immigrants from the UK and Ireland, Canada and other European Countries. Health, education, housing, and social services of immigrants have a greater impact on the government in enacting the laws, particularly immigration laws.

The main threshold period in terms of the countries of origin of the immigrants in US is associated with the Immigration and Nationality Act of 1965, which abolished discriminatory "national origins" restrictions on immigration that disadvantaged potential immigrants from Southern and Eastern Europe and especially from Asia. Due to the continuous flow of migrants, the US is changing its laws from time to time and trying to defend the each immigrant.

The September 11, 2001 terrorist attacks are a stigma on the history of the US. Its impact on national security posed to new challenges. Unauthorized immigration has also been identified as a major threat, and it made the immigrants scapegoats and they are viewed as threat to the American way of life. This incident has changed the shape of majority of laws; especially, border control enforcement, US began tightening the citizenship, and immigration laws to protect their nation from aliens and terrorists.

The Government in the later period of the 1980s and the early 1990s and after September 11, 2001 attacks, faced major policy questions, which were generated by global forces like rationalizing the illegal and undocumented immigration. The Secure America and Orderly Immigration Act is a comprehensive reform, which rationalizes the country's immigration laws and makes them more just, more human and more enforceable. The Alien and Sedition Acts of 1798, the Civil Rights Act of 1964, the Refugee Act of 1980, the Immigration Reform and Control Act of 1986 [IRCA], the Immigration Act of 1990, the Life Act, the USA Patriot Act, the federal Real Id Act, the Convention on the Elimination of all Forms of Racial Discrimination [the "Race Convention" ratified by the United States in 1994], the Border Protection, Antiterrorism, and Illegal Immigration Control Act of 2005, and the Secure Fence Act of 2006 etc., have been enacted to control the illegal and undocumented immigration and also implements the immigration laws without affecting the human rights of non-citizens. The conquest of world poverty and its achievement are the UN Millennium goals. The immediate spur in this is the astonishing size (about double official aid flows) and rate of growth of remittances, income transfers from workers abroad to their home countries.

To safeguard the interests of legal immigrants, the US government has enacted various immigration laws without any discrimination, irrespective of their religion, caste, and color, equal opportunities, and wage equality, etc. The Bill of Rights and other parts of the Constitution also protect the life and liberty of the non-citizens. Social security benefits are also provided to new legal immigrants who legally enter the United States.

International Organizations like United Nations Organizations, International Labor Organization Conventions, International Human Rights Commission, Global Commission on International Migration and International Organization for Migration are making efforts to uphold the interests and rights of legal immigrants and the US Government is also endeavoring to enact flexible immigration laws. This book presents various immigration laws and highlights the existing US immigration laws; the role of legislation to deal with the immigration issues, and focuses on immigration reforms.

The book "The U.S. Immigration Laws: A Debate" contains eight articles collected from different parts of the world. It discusses the origin of the United States of America, the historical background of the birth of the American culture and the impact of immigration on the US culture and its identity, the concept of whiteness, racism in the US, effects of unauthorized migration on national security, the present immigration legal system, flaws and possible reforms, downsizing the illegal migration, changes in immigration laws after September 11, 2001 terrorist attacks, social security benefits of new legal immigrants, positive impact of legal immigration on social security in the United States, European Union legal system in relation to human rights, related case laws, rights and remedies in the protection of legal migrants by various means etc.

The article "Immigration and American Culture: The Struggle for National Inclusion and Identity" by Virgilio Perez Pascoe focuses on the historical background of the birth of the American culture and the impact of immigration on the US culture and its identity. At the end the author analyzes the facts, myths, and public policy related to immigration, solving the issue of undocumented immigration while highlighting related case laws.

The article "Today's Immigration Legal System: Flaw and Possible Reforms" by Rick Fang-Chi Yeh is divided into three parts, which discusses the overview of the immigration legal system, present position of immigration laws, flaws and remedies in the United States legal system. The current system of immigration adjudication does not incorporate the doctrine of separation of powers and the executive and legislature control over it. In order to correct the basic flaws, the four remedial proposals, and related cases laws have been highlighted.

The article "US Immigration Reform: Can the System be Repaired?" by Marc R. Rosenblum, mainly recommends changes to the legal permanent and temporary admissions systems to encourage the recruitment and maintenance of immigrants in the US, and emphasizes on changing the legal visa policies of America. The author also highlights the various recommendations to protect the temporary and permanent migrant workers, enforcement of immigration laws and national security.

The article "Learning to Become American: Immigrants, Race Relations, and Generational Change" by Hartmut Keil focuses on the concept of whiteness, race and racism, and defines the terms like civil rights and naturalization. There is a work competition between different immigrants and they are differentiating with skilled and unskilled immigrants in the labor market. Finally, the author discusses the German immigrants and compares them with the African American immigrants.

The article "Downsizing Illegal Immigration: A Strategy of Attrition through Enforcement" by Mark Krikorian discusses rationalizing illegal immigration by a strategy of attrition through enforcement of immigration laws in United States, This has two main policy implications. After September 11, 2001 attacks, United States is concentrating more and more on border security and particularly laws relating to immigration. The author also highlights the various laws, which have been enacted recently to reduce the undocumented migrants.

The article "Immigration Reform, National Security after September 11, and the Future of North American Integration" by Kevin R. Johnson and Bernard Trujillo focuses on the consequences of international terrorism, and suggests steps to improve legislative action, and the changes made in immigration laws in US after September 11, 2001. Finally the author highlights the related case laws and the role of judiciary in terms of national security and public safety.

The article "Legal Lines in Shifting Sand: Immigration Law and Human Rights in the Wake of September 11" by Daniel Kanstroom focuses on the lines drawn between citizen and non-citizen, war and peace, the civil and criminal systems, as well as the US territorial protection. The Bill of Rights and other parts of the Constitution safeguard the life and liberty of non-citizens, and examine the role of Government to implement immigration laws without affecting human rights of non-citizens. The author highlights related case laws, and the European Union legal system in relation to human rights.

The article "The Contribution of Legal Immigration to the Social Security System" by Stuart Anderson focuses on the Social Security Administration [SSA], and new legal immigrants, who entered the United States, and their social security benefits. SSA is one of the effective functions of the Government. SSA Actuaries provide the data on the impact on social security and different scenarios. According to SSA, there are five legal immigration scenarios. For each scenario, there are two ways to prevent the impact of changing the level of legal immigration. The author also presents the positive impact of legal immigration on social security in the United States.