Asic's do not actually strengthen the netwerk.
Actually, they do.
The technology is available to ANYONE, that includes potential people with bad intents.
If someone wanted to kill the bitcoin network 2 months ago, he had to go buy a million graphics cards, motherboards to plug them in, and about enough powersupplies so you can use them as bricks for a special powersupply-skyscraper. If he would be able to work out a special deal with his local nuclear powerplant (which you can't just do all of a sudden), he would be able to power his army and fork that blockchain.
All someone would have needed to do 2 months ago... well more like 4 months ago, and going back 4 years... would have been to make a few ASICs. Just a few! Now an attacker would have to make many, many ASICs.
Now, all he has to do is go to BFL or another asic company and order a big bulk of asic's. They will probably be willing to give big price reductions.
Exactly... now an attacker would have to order a 'big bulk' as you put it. That's way up from the very small amount that were necessary before four months ago. Furthermore, a botnet is no longer any kind of threat.
The actual point you have come closest to making is that the network is more vulnerable now than it will be in the future. There is no know technology that can supplant ASICs anytime soon. However, the cost to mount a 51% attack is HIGHER now than it EVER WAS. And it is getting higher every day. Now, would bitcoin be more secure if humans didn't have knowledge of ASICs, or if somehow the laws of nature prevented them from being? Maybe. But that is not the case. In this world that we actually live in, the cost for a 51% would have been no higher than the cost of designing and manufacturing ASICs. This was possible back in the CPU and GPU days and is still possible now. Now an attacker would have to actually ramp up production to make enough chips, and by then end of this year the cost of that attack will be many $10's of millions of dollars. And it will cost more than just the silicon, getting everything connected is expensive too.
But i don't disagree. People should be buying asics now, because the technology is out there and not using it would give those malicious people an advantage. In a way, bitcoin is forcing us to further feed it's hunger for higher Hashrate, and if we don't obey the hungry beast and give it it's cookies it's gonna get mad and explode. So far the notion of "bitcoin, freedom to the masses, democracy in it's purest form!"
This is why i think new evolutions in the field (like scrypt and the newest primecoin hashing system) are important and interesting.
I agree with this. But the technology has essentially always been there. Bitcoin mining ASICs are comparatively not too difficult to design, so an attacker could have made bitcoin ASICs three years ago if they had wanted.
