When it comes to international standards I should remind everyone that the NSA doesn't need to do much to make those complicated and unwieldily. Look at SOAP or UML. For some reason when you gather an international consortium together to make a standard it is natural for it to be a huge WTF by the time it eventually becomes finalised. People feel the need to cater for every conceivable use case even if they're unlikely to be practical or real-world and often those pushing for things have very little grasp of the implications.
Crypto related standards are different though, because you actually need people who know what they're doing. So apply the same approach to security and the resulting standard is bound to contain weaknesses. I would bet money that the NSA probably saved the IPSEC standards committee from making it overly weak (much like they enhanced DES when it was first created).
Is there an open source alternative to IPSEC that has been scrutinised by cryptographers?
