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Global warming is defined as an increase in the average temperature of the earth's atmosphere. This trend began in the middle of the 20th century and is one of the major environmental concerns of scientists and governmental officials worldwide. The changes in temperature result mostly from the effect of increased concentrations of greenhouse gasses in the atmosphere.
As far as politics go, the responses are just as varied. Mitigation is common and calls for a reduction of emissions and less reliance on fossil fuels. Coal burning power plants are now replaced with hydraulic power plants and electrical cars are replacing some gasoline efficient cars. Many people, however, feel that this is not enough.
The border itself between Mexico and United States is fraught with a mix of urban and desert terrain and spans over 1,900 miles. Both the uninhabited areas of the border and urban areas are where the most drug trafficking and illegal crossings take place. Crime is prevalent in urban cities like El Paso, Texas and San Diego, California.
Free trade is an economic policy under which the government does not interfere with trade. No tariffs are applied to imports or exports, and people are allowed to trade goods and services as they please. Supply and demand dictates the prices for which goods and services sell and are the only factors that determine how resources are allocated in society.
Unlike the United Kingdom, which has taken a relatively restrictive approach to the possession of arms, the United States has taken a more lenient approach. In the United States, three models have evolved regarding the interpretation of the meaning of the right to bear and keep arms as delineated in the Second Amendment.
Trade unions originated in Europe during the industrial revolution. Because of the machinery that had become commonplace, skilled labour became less in demand so employers had nearly all of the bargaining power. Employers mistreated the workers and paid them too little for the work they did. Trade unions were organised that would help in the improvement of working conditions.