SAN DIEGO , California ( CNN ) -- On the question of whether recent immigrants assimilate as quickly as previous waves , many Americans exhibit short fuses -- and even shorter memories . Ruben Navarrette Jr. notes that immigrants have been criticized throughout history for not assimilating . They have convinced themselves that , instead of adapting to the customs of this country , new arrivals -- most of whom come from Asia or Latin America -- expect the rest of us to accommodate them . They go ballistic over little things -- Mexican flags , taco trucks , libraries that offer bilingual story time , or having to `` press one for English . '' Yet , even as they look down on new immigrants , many Americans look back fondly upon their immigrant ancestors . Legend has it that when grandpa arrived from Ireland , Germany , Italy or Poland , he jumped off the boat , immediately draped himself in the American flag , ripped out his native tongue , and abandoned his culture -- all while singing `` Yankee Doodle Dandy . '' Germans did not move to Milwaukee and make beer and cheese . The Irish did not settle in Boston and join organizations like the Hibernian Society to preserve their heritage and culture . And even while Americans complain about how the current crop of immigrants are n't like their predecessors , they miss the irony : At the time , there were people who said the same thing about their ancestors ; the Germans were thought to not be like the English , the Irish were n't like the Germans , the Italians were n't like the Irish etc . And the Chinese were n't like anyone who had come before them , and so they were labeled `` unassimilable '' by the Tom Tancredos of that era . Some things never change . When I was growing up in Central California , which is home to a large population of immigrants from Southeast Asia , thousands would gather to celebrate Hmong New Year . The local newspaper would do a feature . And , in the days that followed , someone would write an angry letter to the editor complaining that these people were n't melting into the pot . Yet , there is more melting going on than one might think , according to a new report from the Manhattan Institute . Billed as the first annual Index of Immigrant Assimilation , the study was written by Duke University Professor Jacob Vigdor . It measured three kinds of assimilation : economic ( employment , education , homeownership , etc . ) ; cultural ( intermarriage , English proficiency , family size , etc . ) ; and civic ( citizenship , military service , political participation , etc. ) . Far from discovering that recent immigrants are ducking the assimilation process , the study found that `` immigrants of the past quarter-century have assimilated more rapidly than their counterparts of a century ago , even though they are more distinct from the native population upon arrival . '' Of course , individual groups still fall behind in some categories . Chinese and Indian immigrants have low levels of cultural assimilation . Mexican immigrants have low levels of economic assimilation . And Canadian and Indian immigrants have low levels of civic assimilation , since few of them become citizens . But , overall , the news is good . After more than 200 years , America still does an excellent job of assimilating immigrants . Even if a particular group tried to resist the process , they would n't stand a chance . Assimilation happens , whether the immigrants are ready or not . Those are the facts . Of course , fear does n't listen to facts . That is something else that has n't changed . Ruben Navarrette Jr. is a member of the editorial board of the San Diego Union-Tribune and a nationally syndicated columnist . Read his column here . The opinions expressed in this commentary are solely those of the writer .
Navarrette : Americans perceive new immigrants as not assimilating . Americans think ancestors got off the boat waving the Stars and Stripes , he says . Comment: But a recent study says new immigrants are joining the mainstream .