Tom Williams/CQ Roll Call/GettyWhen the government of Israel blocked Reps. Ilhan Omar (D-MN) and Rashida Tlaib (D-MI) from entering the country over their support of a movement to boycott, divest, and sanction Israel, it may have been a public blow to the two lawmakers—but a gift for the BDS movement. The activists who support the controversial strategy to isolate the Jewish state quickly seized on the move as proof that the Israeli government is fearful their movement is gathering steam. They also held it up as further proof for their argument that Israel is a discriminatory state with undemocratic tendencies—one that just bowed to pressure from President Trump, who has openly waged war on the recently elected congresswomen.This week could prove to be a defining juncture for BDS and the broader protest movement against Israel, said Stefanie Fox, deputy director of Jewish Voice for Peace, a Jewish-American advocacy group that favors BDS. “This is a moment that is an opportunit...