Much of the issue hangs on getting the various states to all agree that it needs to be done. The great example of the issues you run into, as well how long it can take, is I-69 — which is approved but still needs to get built from Texas to the Canadian border. Some states in Texas — where the road is needed the most — is moving relatively quickly. Other states, particularly in the middle which are more rural, either are slow walking the project since it isn't a priority for them, where a couple of states just have almost no interest in getting the project built.