Note: The next few sections rely heavily on the work of Gershon Shafir.
There's a lot of shouting back and forth about whether or not Zionism is colonialism. I like to utilize Gershon Shafir's take on the matter: There are many different forms of colonialism, and Zionism follows one of those forms. Let's take a look.
We know that the period from 1880 to 1914 was the time of major colonial expansion throughout the globe. Much of it took this form: a "metropole" with nationalist and capitalist interests claimed control over an area of land, including the resources and people within it, and utilized the people to extract the resources from the land. Since Zionism did not have a "metropole," was not a capitalist undertaking (indeed it was decades before the colonies were even self-supporting, much less money-making), and did not utilize the native population to extract resources (at least as the tale goes), many people say it cannot be categorized as colonialism.
However, not all colonialism followed the familiar model. Colonialism in several parts of the world took the form of "pure settlement colonies," which were "colonies aimed at creating a homogeneous settler-immigrant population." What did this mean? They wanted Europeans to settle the land and extract the resources themselves – without employing (or enslaving) the native populace. The goal of "pure settlement colonies" was to create small European enclaves that would function separately from the native population and promote European national identity in these colonized areas. In practice, the "pure settlement colonies" decidedly altered the local social, economic, and political structure. This form of colonialism took place in Rhodesia (British settlers), Algeria (French and Italian settlers), and Palestine (Jewish European settlers). It is worth noting that although Zionist ideology always envisioned an exclusively-Jewish land, Zionist settlement did not develop as a "pure settlement colony" until just prior to WWI.