As you grow old, you pile up conventions after conventions. You create certain 'ideals', you need your new friend to fit in your definition of that 'ideal'. Those ideals could range from the banal to the sublime. You only want to be friends with people who are of your class, status, match your intellectual wavelength, adventurous, humorous... the list goes on as you add more numbers and white hair (not necessarily in the same order) to your life.
You lose your spontaneity to be friends with a stranger, someone who is totally unlike you or someone who breaks every possible definition of your 'ideal' friend.
Question is why does this happen? You have a motley crew of childhood friends. And honestly, you would have been bored to death if you had friends who were a mirror image of yours! So, why the same rule did not apply as you grew up. Did you stop taking risks?
As one crosses that dreaded threshold of 30, suddenly life no longer seems so rosy as it once used to be. You are faced with immense responsibilities, shouldering the burden of your own decisions, and running after some paper pieces that would buy you 'happiness'. And, you want to guard everything that you have with a mean pride. You want to control, be the conductor of your own orchestra, and do not want even a single note out of tune. And, that's where you go horribly wrong. You are so engrossed in your own little world, the known devil, you forget to even say 'hello' to someone new. Your risk-taking appetite ended with that paragliding jump from the mountain you ran-off from when you were not so 'wised-up'. The unknown is not for you, as you start teaching your kids, "Don't talk to strangers."
But, sometimes you do toe the line. You meet up with someone who makes you want to break your self-imposed rules. You find them interesting, and your eyes light up just the way they did when you were tiny-tots. Yet, you hesitate. Why? Because you fear, you don't want to be betrayed again? By the time you have lived three decades of your life, you know enough about betrayal that you could write a book as thick as the dictionary. And, that's where the real problem starts. You start analysing the person as per your parameters of defining someone as 'trustworthy'. Things remain hunky-dory till you keep ticking off your checklist. But, the moment you cross a pointer, you conclude with vengeance, "I knew it, everyone is the same. I shouldn't have wasted my time and effort."
You run-off to your carefully organised and decorated 'safe' world, get busy with the 'pretend-plays', as a friend once said.
Ironically, you talk of wars and terrorism, and blind hatred almost every day. But have you ever analysed that maybe the start of all these had been because of the walls you created around yourself. When you do not allow people to know you, and extend your hand of friendship to a stranger, do you really think countries will ever resolve their crisis? Think about it, or rather don't and make a new friend NOW!