It's important to note that Einstein lived from 1879 to 1955, and his direct interactions with political figures were primarily limited to his time in the early to mid-20th century. Therefore, it's impossible to accurately predict how he would have specifically reacted to someone like Donald Trump, who became a prominent political figure in the 21st century.
However, based on what is known about Einstein's character and his publicly expressed views on politics, it is reasonable to assume that he would have been interested and engaged in political matters. Einstein was known for his strong humanitarian and liberal values. He was an advocate for social justice, civil rights, disarmament, and global cooperation. He also expressed his concerns about nationalism and authoritarianism.
Given these factors, it is conceivable that Einstein might have held critical views regarding certain policies or actions of political leaders who went against his principles of social justice, equality, and scientific integrity. However, the specific nature of his reaction would depend on the circumstances and the individual in question, making it difficult to make any definitive statements about how he would have reacted to a specific political figure like Donald Trump.