The US should build a wall along its border with Mexico

I. Permit me to begin my discussion of this very important and relevant topic by beginning at the core of the matter. Whether or not we should build a wall or not is entirely related to our fundamental conception of the role of the state. Were we, for example, to adopt an unorthodox definition of the state, such as "The government exists to prevent social inequality", then one might easily find cause to object to a proposal that would prevent the poor in one nation from receiving transfer payments from the better situated nation. However, the statement of the purpose of the state in the United States is outlined in the preamble of the Constitution of the United States, and I quote: "We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity (italics added), do ordain and establish this Constitution for the United States of America." Perceive the beneficiaries of all the purposes of the state; ourselves, and our posterity. Any proposed policy at the federal level ought to be evaluated in the light of its impacts upon ourselves and our posterity. No one need accuse me of nativism as I explain this point of view. It is my actual opinion that immigration is benefits and I would love unlimited immigration just as I love free trade, were it not for the current and projected welfare policies of the federal government. I merely submit that the federal government has obligations exactly commensurate to the extent of the assumption by an individual of reciprocal obligations such as loyalty, service, and dilligence in maintaining social order through upholding legitimately instituted laws upon themselves. It is only when a citizen violates his obligations for example that the government is not merely permitted but obligated to withdraw many of its protections and actively infringe upon liberties previously enjoyed. Foreigners illegally residing within the United States are granted some but not all of those protections, and non-citizens without have negligible consideration. I quote from Matthews vs. Diaz "Neither the overnight visitor, the unfriendly agent of a hostile foreign power, the resident diplomat, nor the illegal entrant, can advance even a colorable constitutional claim to a share in the bounty that a conscientious sovereign makes available to its own citizens and some of its guests. The decision to share that bounty with our guests may take into account the character of the relationship between the alien and this country: Congress may decide that, as the alien's tie grows stronger, so does the strength of his claim to an equal share of that munificence." The constitutional objection to the border barrier based on supposed rights of current or prospective illegal aliens to come in and enjoy our copious "bounty", to borrow the language from Matthew, is thus laid to rest. II.Now, proceeding to the actual matter of the border fence, I salient that I agreed to debate only whether it should be built or not, not whether it should be built while leaving the remainder of immigration policies as they are presently constituted. To completely combat the question of illegal immigration, a holistic approach must be pursued, such as reducing incentives in the form of public benefits, being tougher on employers who employ undocumented workers, tracking better those who receive visas, changing the legal immigration process to make it easier, etc. I will suspend this digression and will only pursue it if my opponent wishes to. Suffice it to say that my proposed policy changes would prevent a simple, uniform, mass migration of illegal immigrants by plane rather than by land. Border barriers exist the world over, and their purposes vary from migration control and terrorism prevention. As a matter of fact, 65 countries either have or are in the process of building border walls. They come from all sides of the political spectrum, be they left-wing social democracies such as Austria and Norway, islamic fundamental dictatorships such as Iran, or totalitarian monarchies such as Saudi Arabia, and many sates in between. This roster includes countries existentially threatened by their neighbors, such as South Korea, countries overwhelmed by migrants, such as India, and countries afflicted by terrorism, such as Israel. While of course the proliferation of border barriers cannot be taken as evidence properly said of their efficacy, in my view, it prohibits a simple dismissal of border barriers based on a few cases here and there of ineffectiveness. This is a global phenomenon happening in nearly every culture group. There is some motivation for this consensus among otherwise radically different societies as pertaining to border walls. I submit that Occam`s razor would compel us to assume the simplest explanation first, that is, that border walls actually function and that seeing as all nations regardless of their political philosophy are self-interested, some element of national self-interest is enhanced by the investment in a border barrier. I therefore propose that in view of this staggering global consensus of governments from such different ideological backgrounds, each privileged with far more data than any casual internet debater, the burden of proof rests with my opponent. It is incumbent upon him to show that border barriers in general and American border barriers in speicifc, are ineffective.III.We may therefore examine some of the more successful implementations of a border barrier, organized by their purposes. I begin with illegal immigration control. To allow my opponent room to make a detailed analysis of my cited examples, I will keep them short and few1. Spain: http://www.bbc.com... ask, how would a horde of 1100 people have been stopped, if not by either extreme violence or the threat thereof, were it not for a physical barrier incapicitating their entry? The walls are considered "generally effective" https://www.thelocal.es...2. Israel: http://www.jpost.com... annual crossings from an average of around 9000 a year to just 16 in 2016. A US fence to reduce significantly the illegal immigrant flow would not need to span the entire length of the border. Simply putting highly effective fencing such as is found in San Diego (http://www.npr.org...) in strategic, high-infrastructure areas would greatly reduce the frequency of border crossings as the financial cost of crossing empty desert and risk to health would dramatically increas, disincentivizing a greater share of potential illegal migrants. IV.Now, allow me to lay out my opponent`s probable argument for him.1. "Many people come by visas!": Both an example of the Nirvana fallacy and refuted by II.2. "Border fences don`t work! People still come across!": Again, Nirvana fallacy. Seat belts do not save every life in a collision, but they reduce significantly.3. "It costs too much!" An additional 3.5 miles of fencing in San Diego is estimated to cost 35 million. (http://www.npr.org...) As an example, if the Rio Grande section, the presently most crossed section of the border were totally walled off, then it would cost 3 billion dollars. That`s no chump change, but remember the cost of transfer payments provided to illegal immigrants. Medicaid expenses alone amount to 2 billion per year. In 1995 with a population of 4.5 million illegal immigrants, their total cost to federal, state, and local governments was 30 billion dollars in 2016 dollars that year. http://www.gao.gov... welfare state has since expanded, as has illegal immigrant population. If the border fence prevented over the next 20 years the crossing of a total of 4.5 million people, it will have paid back over the same period its investment more than tenfold. Per year, nearly half a million people are apprehended, not counting those who evade detection. https://www.dhs.gov...;Summarizing therefore my case, in the mere financial benefits, to say nothing of the anti-terror benefits, the border fence is a solid option for US national interests.