Our warped definition of Christianity is disastrous

What, and how, we think is important; very important.  What we believe in, and what we believe about important topics and issues profoundly shapes who we are.  But there is more to it than what and how we think.  It is absolutely true that an individual cannot be a Christian if they do not believe in Jesus Christ, in other words, they believe that Jesus was the Christ, the Son of God, and that he lived, died, and was raised to new life in order to set us free from sin (enslavement to, and debt because of).  {See John 3:16 as an example of this explained in one sentence}  Belief is not the end of the road.  Belief has to be accompanied by repentance {a turning away from sinful behavior} and has to lead to righteous living {by the power of the Holy Spirit} in order for belief to be effective.  In order for it to be real.  A belief in Jesus which does not change the trajectory of a person's life, in ways both small and great, is meaningless.  Herein lies the problem.  Consider the two passages of Scripture below which together illustrate the absolute necessity of "fruit" (ethical behavior) and give nine prime examples of what it looks like:

Matthew 7:16-20 New International Version (NIV)
16 By their fruit you will recognize them. Do people pick grapes from thornbushes, or figs from thistles? 17 Likewise, every good tree bears good fruit, but a bad tree bears bad fruit. 18 A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit. 19 Every tree that does not bear good fruit is cut down and thrown into the fire. 20 Thus, by their fruit you will recognize them.

Galatians 5:22-24 New International Version (NIV)

22 But the fruit of the Spirit is love, joy, peace, forbearance, kindness, goodness, faithfulness, 23 gentleness and self-control. Against such things there is no law. 24 Those who belong to Christ Jesus have crucified the flesh with its passions and desires.

To say, "I am a Christian" is not enough.  To have a particular political viewpoint is not enough (and often misleading).  To know the key words one should say in order to "sound like a Christian" is not enough.  To attend a church at Christmas and Easter, or even more often, is not enough.  To own a Bible, or even read it, is not enough.  To give money to Christian charities, or the Church itself, is not enough.  A person could have all of those things, and outwardly look the part, but without love, joy, peace, forbearance, kindness, goodness, faithfulness, gentleness and self-control; they would have nothing. {See 1 Corinthians 11}  Don't get me wrong, someone who goes to church, reads a Bible, and gives money to Christian charities is better off than someone who doesn't; but only if those factors eventually lead to the radical change of mind and heart that gives evidence to the presence of the Holy Spirit and results in the outflow from that person's life of the fruit of the Spirit.  If a person remains "associated with" Christianity, but never moves forward, they will actually be worse off on the Day of Judgment for having known better without acting.  {See Hebrews 6:7-8}

The Church in America, in particular, has a self-identification problem.  We've allowed cultural distinctions and political viewpoints to more strongly define our view of what Christianity is than righteous living.  We've minimized the immorality that doesn't bother us, pride, lust, and greed in particular, and allowed ourselves to accept the delusion that anyone who looks the part and is on "our side" in the Culture War is Christian enough.  The Word of God says otherwise.  We will be known by God by our fruit, judged as genuine believers in Jesus, or not, by it. 

Those who mimic the look of being a Christian, without the heart-motivated acts of righteousness to go with it, are either self-deluded or charlatans, either a danger to themselves or to the church as a whole.  As long as we accept those who are "like us" as being good enough because we view Christianity as cultural/political feud to be won, rather than a call to self-sacrificially serve the Kingdom of God that must be obeyed, we will continue to warp Christianity into something which is was never intended to be, with disastrous consequences.