The simple answer is no, you cannot. At least not without some forcing their will on others. No matter what the proposition, if you involve the entire planet in the decision, someone will always disagree. Even if it is as simple as proposing that we should abolish war and resolve our differences peacefully, people will disagree with you. In fact, a vast number of people do oppose that philosophy believe it or not.
Personally I am a fan of diversity and culture, and uniting the world as one would cause us to sacrifice many aspects of culture world wide. Universalizing culture will make cultural variances blend over time causing a loss of holidays, tradition, and people's passion for their homeland (not government) and fellow countrymen. There would be benefits acquired in exchange for these cultural sacrifices, but I fear an over-gentrification of every culture as a result, transforming each region into one completely streamlined corporate society.
When pondering a united world, and considering possible global gentrification, the fear of a New World Order arises, and rightly so. The evil corporate governments of Earth have been pushing for this type of oppressive rule for quite some time, and their intricate plan for a N.W.O. is still being strategically executed right under our noses. They will use whatever rhetorical and persuasive tactics necessary to convince people that having a one world government is a good idea, including promoting world peace and unity as a cover-up to pass more unjust laws that will abolish localized government completely.
If we have learned anything from propositions like The Patriot Act, then we know exactly how governments will spin an N.W.O. policy. They will probably go with something along the lines of The World Unity Accords or The Utopia Initiative, to confuse most people that will not look below the surface, into thinking the proposition will be progressive and beneficial to all mankind.
In reality this type of "unity" is only progressive in that it will be more oppressive, and finally give corporations the opportunity to truly control mankind. RFID chips they plan to implant in people that represent the mark of the beast, will seal the deal, and allow any controlling authority to have complete records of all our movements throughout our lives, including everything from what we eat and the places we go, to the people we love and our personal interests. You may have noticed that it is already like this to a degree, and tracking technology is getting more and more precise as time advances.
In theory it would be quite an amazing feat to see the entire planet unite as one, all agreeing to be peaceful, and respect each other's differences. However as long as there are governments ruling over humanity the way they are now, this type of unity will forever be used against us. If we can collectively free ourselves from the chains of government slavery prior to a one world government scenario, then maybe we can unite the whole world to some degree. But as long as the darkness of empires shadows over the people that sustain it, no kind of real world unity will be possible, accept for an extremely oppressive one, that only benefits those near the top of the pyramid.
And even if there is a perfect scenario where all oppressive governments have been overthrown, and humanity develops unique beneficial systems that work harmoniously with the Earth, there will still be too many opposing opinions for there to be complete unity. Some say that all the separation is what creates so many problems of this world, however it is not the separations themselves, but the reasons for those separations that require a more in depth examination to better understand the roots of our conflicts.
This is the type of thinking that will lead us into a world of more universal understanding. I would like to see a peaceful world without war, with vast diversity and varying cultural distinctions, over a untied world with only one singular way of life that some will still oppose. A united world will always be forcefully united, which is not really unity at all.
In conclusion I will say that changing the whole world can seem like a daunting almost impossible task, but if you focus on changing your world, and positively affecting the little things you can in your every day life, you will be surprised by how much you can inspire others to do the same. That is what changes the world, and it will not happen over night, but if we all start making more conscious decisions for the better, slowly but surely, we will live in a better world, be it a united one or not.
