Of course, assuming that US nationals are superior to other nationals is not biblical. This assumption must be based upon factors that have nothing to do with the real work of missions. Americans enjoy a higher standard of living than citizens of many other nations. However, economic superiority in no way equates to spiritual superiority. In fact, the reverse is often true. Scripture tells us in more than one place that economic superiority usually creates spiritual inferiority (Mt. 19:23-24; Ja. 2:6-7; 5:1-6). The work of missions is about making disciples of Jesus Christ, and poor people often display a greater willingness to follow Christ than rich people do (Ja. 2:5).
The US military is far superior to most other militaries, but Scripture reminds us that the warfare that matters to God is spiritual in nature (Eph. 6:12) and cannot be fought with material weapons (II Cor. 10:3-4). Any honest American believer would have to admit that America is largely losing the battles that matter most to God.
American believers who have had the opportunity to visit countries dominated by Buddhism, Hinduism, and even Islam often see a far greater hunger for spiritual truth than they now see in America. This hunger not only means that the citizens of those nations are more open to hearing the gospel, but it also means that when those citizens become believers, they are more eager to give their lives to preaching the gospel. God is raising up a spiritual army from among our national brethren in other lands to aggressively and faithfully take the gospel to the neediest areas of our world. American believers can either watch these foreign nationals spread the gospel, or we can help them spread the gospel.
Church planters normally have to receive financial support from churches other than the ones they plant. That being the case, Scripture nowhere requires a church planter to limit his support to churches within his own nation. In fact, Scripture actually contains examples to the contrary. The field is the world, and a missionary from one part of the world may draw financial support from a church in any other part of the world.
God has used American missionaries greatly, and they are still needed. In fact, every member of IPM’s Education Department is an American missionary. However, we must avoid the kind of prideful thinking which leads us to believe that American missionaries are more valuable to God than missionaries from other parts of the world. I love America, and I’m grateful to be a citizen of America, but the fact of the matter is that God did not use America as the primary nation to start the modern missions movement, and many current factors seem to indicate that He will not use America as the primary nation to close it.