Takeoffs are optional, landings are mandatory. Let's hope they have a successful mission and a safe return.

or any landing where all seven astronauts walk away from it.

Sad to say, but the examples you cited weren't lives lost in the pursuit of knowledge.

They were lives lost to managerial short-sightedness and corner-cutting.

It's one thing to take a calculated risk when you understand the odds. To take your fate in your own hands. It's totally different to put your fate in the hands of others, who then don't treat the situation with the diligence it deserves.

You wanna try your luck with the Russian space program?

From spaceflightnow.com

T+plus 33 minutes. A few seconds after solid rocket booster separation, a large chunk of something broke free from the external fuel tank. The onboard video camera mounted on the tank showed the object flying away from the vehicle without striking Discovery.

Want to bet that chunk of film is going to be looked at rather closely?

Sky News (UK) have clearly shown an object falling onto the tail of the shuttle as it left the launch pad. The tail knocks the object with enough force to push the object upwards. Question is, is it the same type of object that was shown falling away at booster seperation?Hopefully no damage to the shuttle tail.

I'm excited because my 10 y.o. son is excited. Try living your life a little through your child's eyes. You'll probably lose some of your cynicism and enjoy things like you did as a child again. It's great.

Sorry to rain on the parade, but why exactly am I supposed to be excited about this?

You answered your question in your own post:

I have a son of my own.

I just watched the liftoff with my six year old son. Despite his significant language delay, he told me that he wants to go in space and see how big the earth is. That's why you're supposed to get excited!

No way is it an even bet if humans can compete with the Earth's systems for extinction events.

History shows that the planet is WAY better at it than we could ever hope to be.

Even if we popped all the nukes on Earth, it'd not register on the list of extinction events.

How does NASA know it won't fail in space? Maybe because the entire fuel-tank is useless once they reach space, and the sensors have no function after main engine cutoff? Do you have any idea what the sensors do? Has it occured to you that without knowing these things, as the people who decide whether the lanch should proceed do, your assesment of what risk NASA has taken is meaningless?

Doc, ever manned space launch is a major risk. It wasn't a serious failure, more of a glitch. Something they could live with.

The "gang" at NASA has a little more intelligence than you, that much is obvious.

The model rockets you put together in your Mom's basement, to this day, really don't give you any credibility to judge NASA. Sorry, play again later!

The goal was to inform, not to editorialize, and there was obviously no pressure to "fill in the gaps" left by silence. It really almost gave you a feeling of being there.

You just hit the nail on the head as to what ails American TV broadcast of live events, most commentators don't know when to STFU. You'd never know a picture's worth a thousand words with all the inane drivel being spewed. Sportscasts are the worst in this regard. What I wouldn't give for the ability to filter out the commentators but keep the event/crowd sounds. Sigh...