Trade,Foreign Direct Investment,and Immigration Policy Making 815 The article proceeds as follows.I begin by theorizing how trade openness and increased firm mobility can lead to restrictions on immigration because of their effects on firms.Next,I discuss the ways in which tariff policy and the ability to invest overseas were out of the control of US senators.Third,I provide evidence that trade policy and firm mobility help explain this variation,and I examine the evi- dence for the alternative explanations.Fourth,I provide evidence showing how firm lobbying on immigration has changed with trade openness and increases in firm mobility.Finally,I conclude by discussing the implications of this article for research on other economic policies. Trade Policy,Firm Mobility,and Support for Immigration In this section,I examine how changes in trade policy and firm mobility affect firms' support for openness to low-skill immigrants and how this,in turn,affects policy- makers'support for open LSIP.I argue that immigration policy toward low-skill workers and the policy toward high-skill workers should be studied separately; although,they often get bundled together conceptually and in legislation.16 These policies target two different populations that are not interchangeable.Low-skill immi- grants do not have the skills to take the place of high-skill immigrants and high-skill immigrants are unlikely to give up the wage premium that their skills provide them by taking low-skill jobs.Policy similarly is often used to target these populations;many countries have policies specifically targeting high-skill or low-skill workers.In general,when states are open to low-skill migrants they are also open to high-skill migrants but not vice-versa.17 Further,the flow of low-skill migrants is more politicized than the flow of high- skill migrants.Natives tend to have much more favorable views of high-skill immi- grants than low-skill immigration.18 Nor do these preferences seem to be a new feature of politics.In the United States,for example,most of the anti-immigrant senti- ment has been targeted toward the least-skilled migrant group:the Irish in the 1840s, the Chinese in the mid-1800s,the southern and eastern Europeans at the turn of the last century,and Hispanics today.It is,therefore,politically easier for a politician to support a more open policy toward high-skill immigrants than to low-skill immigration. Although beyond the scope of this research,the politics of high-skill immigration may also be affected by trade openness and firm-mobility as many high-skill occu- pations can be easily outsourced overseas.However,there is less opposition to 16.These policies are bundled together in one piece of legislation for the same reasons that there is omnibus legislation in other policy areas:fragmentation across committees,divided government,and easy minority obstruction.Krutz 2001. 17.Peters forthcoming. 18.For example,see Goldstein and Peters 2014;and Hainmueller and Hiscox 2010. 19.Blinder 2007.The article proceeds as follows. I begin by theorizing how trade openness and increased firm mobility can lead to restrictions on immigration because of their effects on firms. Next, I discuss the ways in which tariff policy and the ability to invest overseas were out of the control of US senators. Third, I provide evidence that trade policy and firm mobility help explain this variation, and I examine the evi￾dence for the alternative explanations. Fourth, I provide evidence showing how firm lobbying on immigration has changed with trade openness and increases in firm mobility. Finally, I conclude by discussing the implications of this article for research on other economic policies. Trade Policy, Firm Mobility, and Support for Immigration In this section, I examine how changes in trade policy and firm mobility affect firms’ support for openness to low-skill immigrants and how this, in turn, affects policy￾makers’ support for open LSIP. I argue that immigration policy toward low-skill workers and the policy toward high-skill workers should be studied separately; although, they often get bundled together conceptually and in legislation.16 These policies target two different populations that are not interchangeable. Low-skill immi￾grants do not have the skills to take the place of high-skill immigrants and high-skill immigrants are unlikely to give up the wage premium that their skills provide them by taking low-skill jobs. Policy similarly is often used to target these populations; many countries have policies specifically targeting high-skill or low-skill workers. In general, when states are open to low-skill migrants they are also open to high-skill migrants but not vice-versa.17 Further, the flow of low-skill migrants is more politicized than the flow of high￾skill migrants. Natives tend to have much more favorable views of high-skill immi￾grants than low-skill immigration.18 Nor do these preferences seem to be a new feature of politics. In the United States, for example, most of the anti-immigrant senti￾ment has been targeted toward the least-skilled migrant group: the Irish in the 1840s, the Chinese in the mid-1800s, the southern and eastern Europeans at the turn of the last century, and Hispanics today. It is, therefore, politically easier for a politician to support a more open policy toward high-skill immigrants than to low-skill immigration. Although beyond the scope of this research, the politics of high-skill immigration may also be affected by trade openness and firm-mobility as many high-skill occu￾pations can be easily outsourced overseas.19 However, there is less opposition to 16. These policies are bundled together in one piece of legislation for the same reasons that there is omnibus legislation in other policy areas: fragmentation across committees, divided government, and easy minority obstruction. Krutz 2001. 17. Peters forthcoming. 18. For example, see Goldstein and Peters 2014; and Hainmueller and Hiscox 2010. 19. Blinder 2007. Trade, Foreign Direct Investment, and Immigration Policy Making 815