Polish Prime Minister Donald Tusk signaled his country will eventually try to obtain its own nuclear weapons as Europe strengthens deterrence amid doubts over U.S. commitment to defending the continent. “Poland takes nuclear security very seriously,” the prime minister said ahead of a weekly government meeting on Tuesday. “As our autonomous capabilities grow, we will strive to prepare Poland for the most autonomous actions possible in this matter in the future.” Warsaw will not be “passive” as it also invests in nuclear power plants, according to the prime minister. Tusk said on Monday that his country was in talks with...