I live just outside DC and have been through there many times. They have plenty of infrastructure already. I find it difficult to believe they need an additional $150,000,000. That's a LOT of zeros. I know there will be a ridiculous number of people there (believe me, I do NOT look forward to driving to work that day), but....
Yes, they have to protect the man, but most of the forces protecting him are ALREADY being paid to do so, and most of the additional security measures are already budgeted elsewhere as well. So what's the $150mil for? Entertainment is probably a huge chunk of it. Port-o-johns only cost so much.