In an interview with the New York Times, Donald Trump suggested that if elected, he might make some changes regarding the level of support the US gives its NATO allies.

In a recent interview with the New York Times, Donald Trump suggested that if elected, he might make some changes regarding the level of support the U.S. gives its NATO allies. 
According to Trump, wealthy nations that do not make satisfactory financial contributions to military efforts are among those likely to no longer receive assistance. 
Said Trump, “I would be absolutely prepared to tell those countries, 'Congratulations, you will be defending yourself.'” 
Those and other comments have filled some with fear that Trump’s policies could threaten the long-standing alliance.
Further, a number of experts believe Trump’s reinterpretations of the multi-nation agreement could encourage Russia to "intimidate NATO allies."