Why are republicans concerned about a nuclear Iran?

[politicus]

Because they would like for the US to be the police power of the world, therefore any threats to its interests are to be taken extremely seriously.

The whole purpose of a nuclear weapons is not to use them, its for defense to other nations to let them know that they should never hurt us/them/whoever. For Iran to use their nuclear weapons (that they don't have, ATM) on Israel and "wipe it off the map" as they say is an so mind mindbogglingly stupid it would start a massive world war, and compared to the United States militarily its a toddler with diapers. I can't imagine them doing it.

Full scale Iranian attack on Israel is not the only problem.

1) Spread of nuclear weapons to Iranian clients and/or allies - incl. non-states.
2) Nuclear terrorism.
3) Making it extremely risky to wage war against Iranian allies (how do you ever get rid of Hizbollah if Iran has nukes?)
4) Regime change with more radical elements taking over.

[politicus]

Nuclear power has shown to be a dangerous and unpredictable source of energy--see Chernobyl, 3 Mile Island, etc.

No.

One of those times where a single word answer is no good.

[politicus]

Nuclear power has shown to be a dangerous and unpredictable source of energy--see Chernobyl, 3 Mile Island, etc.

No.

One of those times where a single word answer is no good.

(lots  of general comment)

In other words, "No."

Can't you see why leaving out the stuff you just wrote and answering with a simple "no" is no good?

If people start arguing for their positions and just write yes and no we are back to kindergarden level of discussion.