That's not an argument, that's something used to get out of one unless you elaborate the hows and whys.
Power, in particular? Status quo is maintained - natives are pissed off, conflicts are not resolved, immigrants have no particular reason or perhaps even ability to vote for the politicians responsible.
Immigration tipping point scenario (natives become a minority, that is) - same but even worse, immigrants have their own politicians to support and empower, natives are still pissed off - even more.
Natives get pissed off scenario? Nationalists get support, current leaders are at best kicked out, if not, well, you know what happens to opposition in case of extreme far-right. Metabolic inviability.
There's two main threads of thought:
a) The government creates a threat narrative (real or imaginary) by causing a bad thing to happen which they can only solve by having more powers. Consolidation of power.
b) The economic suggestion I mentioned before regarding people applying to jobs. Consolidation of money.
Example of a):
1. Say that you need more workers.
2. Have mass immigration.
3. Mass immigration causes social and terror problems.
4. Problems are done over the internet.
5. "We require more government controls on the internet!"
6. Government controls, of course, solve nothing but they have more information and ability to police their citizens lives.