I find it truly amazing that a project with hundreds of millions of dollars at stake could have such a simple bug. After they discovered the first bug, it seems

I find it truly amazing that a project with hundreds of millions of dollars at stake could have such a simple bug. After they discovered the first bug, it seems like they should have sat down to carefully audit all other places where that could happen - because it seems like the attackers certainly did! From reading the article on Smart Contract security (https://blog.ethereum.org/2016/06/10/smart-contract-security/ https://blog.ethereum.org/2016/06/10/smart-contract-security...), I get the feeling that the programming model might be somewhat to blame. The "obvious" ways of implementing something are subtly broken, in ways that are very difficult to anticipate without a very deep understanding of the protocol. The programming model demands that the program be capable of calling functions that are not under the programmer's control, and which can do nearly anything. This is very, very difficult to get right, and very easy to screw up, as anyone who has tried to write a sandbox environment can attest to.