不了解美国的相关情况，说说加拿大，

加拿大联邦法院司法复核，此案中移民申请人通过权宜婚姻获得 加拿大永久居民身份，近一步获得 加拿大公民身份。此案中，加拿大移民部的官员(senior analyst)做出了以下论述：

[31] In doing so, the Senior Analyst made the following determinations: • Statelessness: the Senior Analyst found that while the applicant had lost her Chinese citizenship when she obtained Canadian citizenship, she would not necessarily be rendered stateless, because China has a legal process by which former nationals can apply for restoration of their status. However, as a positive decision cannot be assured if the applicant applied for the restoration of her Chinese citizenship, the Senior Analyst took into account the hardship that the applicant could face should the decision render her stateless. The Senior Analyst noted that while Canada is a signatory to the 1961 Convention on the Reduction of Statelessness ([1978] Can. T.S. No. 32, 989 U.N.T.S. 175, in force December 13, 1975), which generally obliges a contracting state not to deprive a person of its nationality if to do so would render the person stateless, the Convention also provides that a state may do so “where the nationality has been obtained by misrepresentation or fraud”: see Article 8(1) and (2) of the Convention.

联合国🇺🇳减少无国籍状态公约第8(2)表示，“通过虚假陈述或欺诈手段获得公民权”并不受该公约保护。加拿大联邦法院还讨论了其它内容，有兴趣可以打开链接自己查看此判决书。

Xu v. Canada (Citizenship and Immigration), 2021 FC 1102 (CanLII) https://www.canlii.org/en/ca/fct/doc/2021/2021fc1102/2021fc1102.html