The Gadol of Minsk writes in a halachic response regarding the settlement of Eretz Yisroel: "This mitzvah is different from all others. All other mitzvos are absolute personal obligations: every single Jew must do them, without any conditions or limitations. The mitzvah of settling Eretz Yisroel, on the other hand, devolves only on the Jewish people in general, and it has limitations. Chazal foresaw with their holy inspiration that if this mitzvah were given over to all and were set up as an obligation for everyone, the people would burst in unlawfully and immigrate by force, without any planning or sensibility. From the corners of the earth there would stream Jews by the thousands, and they would then commit two wrongs. 1) Since they would have no reliable source of income, they would struggle against one another for money, crime would increase and poverty would be rampant. Destitution would drive the Jews to go against their own best judgment and against their Creator; they would defile the holiness of the place, strip the land of its honor, and the losses would outweigh the benefits. 2) Such a movement of awakening could lead to a spirit of rebelliousness against the just kings of the earth under whom the Jewish people live. The Jews' evil inclination and irrational behavior would induce them to throw of the yoke of their government, and leave in a rebellious manner. Then the hearts of the rulers would turn against the Jews, they would remove their protection from them and the Jewish people would be subject to persecutors and plunderers.
Therefore, Chazal informed us that Hashem made Israel swear not to go up as a wall (which Rashi explains to mean together) and not to rebel against the nations - and according to the above, the second oath is the reason for the first. Through this oath, Chazal weakened the power of the mitzvah [to settle Eretz Yisroel] and limited its scope due to the needs of the times. This is an example of the principle, 'When it is time to act for Hashem, they annulled Your Torah' (Tehillim 119:126)."
To counterbalance this, Chazal broadened the mitzvah of settling the land and placed it upon the Jewish people as a whole. Over the course of time, a wonderful, lasting solution for how to fulfill this mitzvah has developed: the Jews of the Diaspora lands honor Eretz Yisroel with their money by making regular contributions to the support of that tiny number of poor Jews who live in Eretz Yisroel. This is the rationale behind the Rabbi Meir Baal Haness fund, established in all our countries, which the Jewish people have accepted upon themselves as a permanent law. Thus some fulfill the mitzvah with their money, and others with their bodies." (Printed in Sinai v. 6, p. 213)