So you're saying that illegal immigration impedes the ability of a society to build collective capital.
Discussion
What is collective capital?
The primary role of modern governments is to act as insurance: social security, unemployment insurance, welfare, ect. These are the collective pools of capital ($) that individuals pay into. As unproductive illegals make claims on benefits that they did not contribute to; they overload and crash the system. It's basically the Cloward - Piven strategy.
If people want to buy insurance, they should be free to do so. If people want not to buy insurance, they should be free to abstain. Insurance companies ought to compete for customers based on services and costs.
The State is that entity which funds its operations by coercing the labor of its subjects. It is not necessary for an insurance provider to also hold a territorial monopoly on violence.
I'm not going to disagree with you. This book is probably the best descriptor of transitioning to a private insurance model: https://mises.org/library/private-production-defense