A DWI conviction may have significant immigration consequences. Specifically, such a conviction will greatly decrease the chance of you being able to return legally. There are several reasons for this.
First the conviction could make one inadmissible on health-related grounds as it could be considered evidence of alcoholism. As a result, it could trigger the health related grounds of inadmissibility under 8 USC § 1182(a)(1)(iii).
Additionally, while driving while intoxicated is not a statutory bar to admission, it is a negative factor in discretionary immigration determinations, which, in fact, most immigration decisions are. In many cases, adjudicators base discretionary denials on past convictions for driving while intoxicated. Although this is not the place for an exhaustive overview of the case law, there are many examples to choose from. Kouljinski v. Keisler, 505 F.3d 534 (6th Cir. 2007) (upholding a discretionary denial of asylum because the applicant had three driving under the influence convictions); Matter of Mejia Ramirez, 2014 WL 4407664, at *1-2 (BIA Aug. 22, 2014) (rejecting “respondent’s argument that a driving while intoxicated conviction must be treated as trivial for discretionary purposes).
In the case of deportation decisions, a DWI conviction would also be considered negatively at a matter of discretion if the deported individual were to apply for a visitor’s visa in the future or try to immigrate to this country through his United States citizen family members over the age of 21, who may petition for visas for family members who have been deported to re-immigrate to the United States as permanent residents.
So to answer your question, a DWI conviction carries the potential for serious consequences not only with regard to deportation but also concerning re-entry into the country.