The answer, I believe, is twofold: controlling the borders, however imperfectly;

我认为，应采取双重应对之道：控制边境，尽管这种做法存在缺陷；

youdao

Indeed, regulators remain concerned about controlling the flow of speculative capital across borders.

事实上，监管机构仍关注于控制投机资金的跨境流动。

youdao

The 2.0 Party must insist on controlling our borders and (like every other country in the world) making it infeasible for people to live and work in the U.S. illegally. (Illegal immigration is a form of identity theft, and the same system that will defeat identity theft will defeat illegal immigration.) However, it should not support numerical limitations on legal immigration.

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Mr. MOUWAFAK AL-RUBAIE (Iraqi National Security Adviser): To reach out and tell them that, look, if you don't engage constructively and positively in Iraq, if you do not help the national unity government in controlling the violence and defeating al-Qaida and its affiliates, this violence will spill over across the borders.

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Mr. CHRISTIE: Well, Farai, for having worked for both the vice president and the president of the United States, they are both very concerned about controlling our borders.

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