Entering US with nuclear bomb is no problem

The reality is that the United States is a rather large landmass surrounded by a multiplicity of potential entry points and methods. It is impossible to stop terrorists from importing dangerous materials and/or personnel into the country entirely, and all it ever takes is one small team to cause untold havoc. This demonstrates that the need for a more comprehensiove approach to security, namely co-ordination with allies (as opposed to attempts of dominating allies), effective tartgeting of terrorists through more than just military means, and the creation of a stable global environment are going to be what stops terrorists.

Jam it back in, in the dark.

I didn't say that at all, I was tryign to convey that simply focusing on physical border security is bad if you're trying to imporve border security.

There's nowhere I can't reach.