There's a couple points outside of the terrorist angle to consider since this is has been framed around rape, murder, property crimes and drug distribution:
We're in a net decline of illegal immigration....more are currently leaving than coming
66% of illegal immigrants in the US currently have resided here for 10 years or more
Statistically the percentage of immigrants who are criminals is about the same as the non-immigrant population (but you'd never know it from the bad dudes rhetoric)
Crime is still on the decline (but you'd never know it...)
Govt focus on deporting criminal immigrants has resulted record numbers of deportations while sanctuary cities have exited
Sanctuary cities cite the positive impact of the policy increasing safety by encouraging illegal immigrants to interact with authorities
Net economic effect and role of illegal immigrants in the economy
Choice 1 is eliminate sanctuary status and there's no guarantee that immigrant crime rate will go down. There is plenty of speculation that the opposite could be true.
Choice 2 is eliminate funding to city law enforcement and there's no argument on what the impact of that will be