Throughout time, borders have always shown where one tribe, hamlet, or country ends and another begins. The border can show how much territory a group claims as theirs. It can also show the distinction between cultures or languages.
Europe is the perfect example. There are dozens of small countries, each with their own language and culture that has a border around their land, showing where one group ends and another begins. Most of these countries share a similar currency, the Euro, and all of the other countries share the Pound. This way, when someone wants to go into another country, they won't have to waste time changing their currency over when they should be using their time exploring and learning about their new surroundings.
When the idea of a separating between countries was made, this was the eventual goal; for there to be peace between countries so people can learn about their neighbors safely while still keeping their own culture in a separate area so it can stay preserved.
Currently, The US has the wrong idea. They are so concerned about preserving their racist, misogynistic, close-minded attitude that they are refusing to learn that it is okay to let cultures intermingle without trying to start a war over it.
The mindset of the US is that "we should keep our people separated to the point where everyone's individual countries become only what they know. This way, Those Damn Aliens won't ruin my country." What the US isn't realizing is that their country was originated by aliens.
All throughout American history, our country has shown that we were made for helping those less fortunate than ourselves when they come into our country. We have always been making sure people get jobs, show their individuality, and live the American Dream where anyone can be anything and can do anything that they put their heart into.
Where has that mindset gone? It became lost when segregation took over, when a hatred for anything different than ourselves slithered into the minds and hearts of a people that was bred for making the American Dream a possibility for anyone, even people who weren't born American.
Maybe if people actually opened a history textbook once in awhile they would realize that their bigotry is what is making them un-American. Maybe then our now cold-hearted people would open their sewn shut eyes and realize that, over time, our people have become as un-American as possible when we should have been growing towards peace.
We should have been growing like Europe, learning to accept the differences of the countries that border us and using those differences as an educational experience for our youth so they can become more open-minded than our generations now.
Maybe one day our children will teach us that in order to become more American, we must accept that the American Dream applies to every American, Alien or animal that enters our land and decides that they want to change for the greater good. That way, we can once again open our gates, willing to expand our country into the utopia it was meant to become, not forcing her down the route of hatred we're trying to coerce her down now.