Faith and religious belief are not as simple as a name, a divinity, or a book. The range and diversity of faith systems -- including denial of faith -- that are extant on this globe is staggering. Even within what are considered "main" religions (Christianity, Judaism, Islam, Hinduism, Buddhism, et. al.), there is a breadth of belief that encompasses a multitude of variations on the main religion's themes.
The Founding Fathers were well aware of this, and of the strife created where the State imposed a religion upon its people. Therefore, the First Amendment to the Constitution enjoins the U.S. government from establishing a national religion. In doing so, it limited the ability of the government to proselytize for or cater to any one religious belief system, and simultaneously separated religion from government, so that no one religious faith could hold sway over the entire country, save by unanimous acclamation, a situation unlikely to happen given the diversity of the citizenry.
So, each to his or her own. Whatever faith fits your circumstance best is yours; your right to it is assured. That said, this will not stop others from attempting to use their faith as an exemplar of the "right" religion, for you and for everyone else. This leads to some very thin ice.
Faith is individual. Even in relatively homogeneous religions, how you choose to interpret them, how you choose to worship, how you exercise your faith, is entirely up to you. Some will follow the tenets of their religion to the letter; others will pick and choose what suits them. Some will follow religious leaders blindly; others will question what is said in light of what they know. Your faith may fall under the umbrella of a particular religion, but how you choose to worship (or not) is entirely your decision.
This sets up friction, between those who interpret religious teachings more rigorously, and those who do not. In every religion, this leads to some form of fundamentalism, which expresses itself in various fashions, depending on the teachings of that religion. This friction is often expressed in actions, as members of orthodoxy seek to spread their faith outward and impose it on others, sure of its "rightness." Such efforts put a strain on our secular life, imposing conflict and sometimes danger.
This conflict is nothing new, and the secular world and the religious world have done this dance for eons, it seems. That the United States should be founded on the ideal that religious freedom is a right, and religious tolerance is sacrosanct, has proven to be both a bold move and a ramping up of the dance. It is not often easy for some to understand that no matter how fervent their belief or faith, not everyone is willing to share it, and no one is under any obligation to give it consideration. What works for one group, may not work for another.
The constant push-and-pull of religious faith versus secular society could weaken us, not unlike what happens when a spoon is bent repeatedly until it breaks. We need not let this happen, however, for the answer lies within each of us: the belief in liberty. We sometimes take for granted that we can even have such conflict, given the history of humankind is replete with examples of the imposition of religious dogma, or the brutal ransacking and destruction of some faiths by secular oppressors. If we cherish the hard-won liberty that is now ours, then we must see that it is enough that we believe in a thing, and if others believe it, so be it. This is true in so many other arenas, and while this may be difficult to employ in regards to religion, we would do well to consider the consequences if we do not. Liberty has fallen under less.