A primary source of anything is a first hand account be it a diary, eye witness account, the person must have experienced it themselves while a secondary the information could have been passed on for example a news paper or memoir on someones life.
When Mexico achieved its independence from Spain in 1821, New Mexico became a province of Mexico, and trade was opened with the United States. ... Two years later, the Treaty of Guadalupe Hidalgo ceded New Mexico to the United States, and in 1853 the territory was expanded to its present size through the Gadsden Purchase.
There have always been conflicts between individual rights and national security interests in democracies. Limits on civil liberties during wartime, including restrictions on free speech, public assembly, and mass detentions, have been the most serious threats to individual freedom. Even in peacetime, counter-terrorist measures including profiling, detention, and exclusion, along with the use of national identification cards, have raised concerns about racism, constitutional violations, and the loss of privacy. With the passage of new anti-terrorist laws after September 11, 2001, these tensions have increased. Supporters of broader governmental powers insist that they are part of the increased security measures necessary to safeguard national security. In contrast, many civil rights groups fear that the infringement upon individual rights is another step in the erosion of democratic civil society.
Wartime measures. The severest restrictions on civil liberties have occurred in times of war. In September 1862, during the American Civil War, President Abraham Lincoln (1809–1865) suspended the right of habeas corpus in order to allow federal authorities to arrest and detain suspected Confederate sympathizers without arrest warrants or speedy trials. Well aware of the drastic nature of such a step, Lincoln justified it as a necessary wartime measure. After the United States Supreme Court found Lincoln's abrogation of habeas corpus an unconstitutional intrusion on Congressional authority, Congress itself ratified the measure by passing the Habeas Corpus Act in September 1863. Through 1864, about 14,000 people were arrested under the act; about one in seven were detained at length in federal prisons, most on allegations of offering aid to the Confederacy but others on corruption and fraud charges.
Read more: http://www.faqs.org/espionage/In-Int/Intelligence-and-Democracy-Issues-and-Conflicts.html#ixzz4XX37pHRv
