Have an Answer?
This is a thoughtful question and deserves a thoughtful answer. I shall try to do my best and be helpful. The challenge in answering is that the topic of homeland security / political science jobs is VAST... Why? Because the business of government especially as it relates to homeland security policy and where the lines are drawn between federal and state homeland security is fodder for years of consulting work.
Homeland security covers an spectrum of disciplines ergo, job positions and careers including law enforcement , immigration reform, and balancing the need for trade across our borders. It involves policy, budget, information technology, procurement, and ways to manage seized property as well as dealing with prisons, as an example. To understand homeland security is to view it as business and bureaucratic ecosystem unto itself. I know this to be true because I sold to the department of homeland security for many years and have an appreciation for the magnitude of what they accomplish and the equally immense size of the infrastructure they need to execute their mission.
If you want a job at D HS, it's hard to get one because the hiring process for the Feds is ridiculous. But that being said, just checking out their website, you can get a feel for what's out there. Add to that the policy work on the hill supporting DHS.. And the ecosystem of contractors the government spawns.... The opportunities could be limitless. The question you need to ask is, how patient are you in understanding DHS. Clearly. The jobs there will be unique as they are delivering a service that is policy and compliance... Not profit or growth oriented. Measuring success may be difficult unless it's measuring how many illegal drugs you've confiscated. And yes, there is inherent conflict between DHS and DEA/ DOJ. Different agencies with similar goals.
The other thing to consider is the state and local levels where they work with the federal homeland security. A position I. One may have counterparts at the state level. Being able to get a toe hold at either level helps you.
Happy to give more thoughts. Let me know. It was my old storming ground when I was in High tech federal sales .