1. Answers that seek to change the question.
Blaming humans for damaging the earth
References to "the fall"
Slippery-slope arguments such as, "if god prevents a tsunami where does he stop?"
Any answer that appeals to free-will.
The question of this thread is very specific. It only concerns "natural evil". In theology this term relates to suffering that is not caused by human actions. Earthquakes and tsunamis have been happening for millions of years before humans appeared. They are a result of plate tectonics. They are not caused by anything humans have done.
If god chose to do so he could refuse to stop suffering caused by human actions while preventing the negative consequences of how he chose to make the world. Either directly or indirectly, the tsunami was entirely an act of god.
If god had calmed the wave before it had even reached the surface no human would ever have known about it and no free will would have been effected in any way.
2. Answers that call into question god's ability to prevent the tsunami
There may have been unforeseen consequences of stopping the disaster
God is not all-powerful
The god of theism is the omnipotent creator. It would have been trivially easy for him to calm the wave and prevent any other negative consequences.
The question is not a problem for worshippers of a lesser god.
3. Answers that seek to shift the blame
People should not have lived so near the sea
People should have known how to read the signs
Humans do bad things too
Satan did it
This is morally equivalent to throwing rocks at a crowd of people and blaming them for not ducking. It portrays god as vindictive and unloving.
The people who drowned were not living on top of a fault-line or beside a live volcano. The tsunami impacted on thousands of miles of coastline around the Pacific Rim. Most of the victims had no opportunity to take evasive action.
Measuring the morality of god against that of human tyrants is setting the bar low for the god of christian theism.
The concept of god's nemesis doesn't even appear in the bible until post-exile when the Jews came into contact with the dualistic Zoroastrian religion. It is a strange pagan notion that makes god look pathetically weak.
Theism does not teach that god handed over his entire creation to a diabolical enemy with no restrictions. The devil can do nothing without the knowledge and permission of god. If Satan caused the tsunami he did so with the full knowledge and permission of god.
This answer is the moral equivalent of letting a wild lion loose in a village and then blaming the animal for the deaths.
4. Answers that seek to find some benefit in the disaster
Suffering makes us stronger
Suffering teaches us compassion
It afforded the opportunity for people to offer help
These are Ivory Tower responses that takes no account of the reality of human suffering. A quarter of a million people learned nothing from being drowned. Their hopes and dreams perished in a moment. Hundreds of thousands of survivors were left bereaved and without homes, jobs or the necessities of life.
Human efforts to clear up god's mess does not excuse his passivity. It is also astonishing hubris that diminishes the lives of a quarter of million people into a commodity to be used for the benefit of producing better christians.
5. Answers that try to reject the question
Who are we to judge god?
God can do whatever he chooses
We just need to trust that whatever god does is for the best.
This answer requires that we unhitch the word "love" from any meaningful definition. We may think we know what love means but god demonstrates that we have not the slightest idea. Love could just as easily mean the capricious annihilation of a quarter of a million innocent people. It destroys our ability to make moral judgements. "Good" is whatever pleases god from moment to moment. Mass destruction is just as morally good as altruism and self-sacrifice.
If god is love, everything he does must be motivated by love, even when he judges. Love is not a hat he can take off for a while and replace with one labelled "vengeance".
Ethics become a matter of divine fiat and the value of human life is trivialised. This defence reduces god to a celestial Pol Pot who may choose on a whim to eradicate our lives in the manner of the killing fields of Cambodia.
Imagine you thought you knew a friend really well. You knew he was capable of being kind and generous as he had demonstrated many times. Then to your horror you discovered he regularly beat his wife and children. You had proof to this effect. It would be foolish of you to overlook his violence as if his moments of kindness made it of no consequence. You would need to put your emotions aside in order to form a more honest appraisal of your friend. Similarly believers need to face up honestly to god's abuse of the human family he claims to love.
If neglecting to stop a wave that drowns a quarter of a million people doesn't give us pause to reconsider the wisdom of blindly trusting of god what would?
6. Answers that Retreat into temporary Deism
This is not god's time to intervene
God has promised to end suffering at a future time
According to christian theism, god is intimately involved in human affairs. Not just in giving strength to cope with whatever happens in life, but in actually changing events for the benefit of those who ask in faith.
"If you remain in me and my words remain in you, ask whatever you wish, and it will be done for you." - John 15:7
"Dear friend, I pray that you may enjoy good health and that all may go well with you , even as your soul is getting along well." - 3 John :2
Even the phrase"give us today our daily bread" proves conclusively that god is active in the world. Anybody who does not believe this is not a christian theist and has taken refuge in deism.
If all christians comply with Jesus' words to petition god for things, and imitate John by praying that god bless and prosper others, then god is active every second of every day responding to millions of requests. If god answers even one of those prayers it destroys the argument that god was not in the intervention business on 26th December 2004
Focussing only on a long-term plan to end suffering does not address the question. A believer still has to show how stopping the tsunami would have hindered that plan.
7. Answers that trivialise the reality of human suffering
Suffering will be unimportant compared to eternal rewards
This is ethically repugnant. Suffering is not reducible to arithmetic. This life really matters. Any philosophy that minimises the importance of physical human life is dangerous. It is the same mentality that leads to religious extremism and flies aeorplanes into tall buildings.
It is an extreme example of "the end justifies the means" defence, so beloved of tyrants.
Like other theodicies it is dehumanising by reducing humans to pawns in god's game.
Imagine that scientists developed a pill that would eradicate all unwelcome memories and create a feeling of bliss. How would you judge a scientist who imposed the most horrific suffering on millions of people, as unwilling subjects of his experiment, but who offered some of his victims of the magic pills when it was over?
8. Answers that make a virtue out of "Mystery".
God's ways are higher than our ways
There may be reasons that we are not capable of understanding
Thesits cannot take refuge in mystery without being deeply dishonest. Deists and agnostics can get away with it; they only ever make very modest statements about their knowlede of a deity. Theists are extravagant with their knowledge claims. They claim to know all sorts of things about god's nature, qualities and preferences. So when somebody points out a fact about reality that seems to contradict some of thse claims they cannot suddenly cry "inscrutability". The one option that is not open to a theist is feigned ignorance, not with all those things they already claim to know. That would be like a rich man pleading poverty when its his turn to get the drinks in.
The knowledge claims that theists make for god create the following paradox...
A. God observed the Asian tsunami as it evolved
B. God knew it would kill a quarter of a million people and displace 5 million more
C. God had the power to stop the tsuanmi
D. God did not stop the tsuanmi
E. Everything that god does is perfectly loving
Therefore allowing a tsunami to drown a quarter of a million people is a perfect act of love.
But this contradicts everything that christianity teaches about love. Jesus greatest command was "do unto others as you would have them do unto you".
If we failed to prevent the violent death of others when it was within our power to do so we could not reasonably claim to be following Jesus' greatest command.
Therefore christian theism is fatally flawed, not only because of external evidence but because it is internally inconsistent.