(Bloomberg) — Want to receive this post in your inbox every day? Sign up for the Balance of Power newsletter, and follow Bloomberg Politics on Twitter and Facebook for more.President Donald Trump is signaling he’ll fight tooth and nail against Democrats’ impeachment efforts, by disparaging a whistle-blower complaint stemming from his controversial phone call with Ukrainian President Volodymyr Zelenskiy and telling donors behind closed doors, “We’re at war.”Defiance was the watchword of the week in the U.K. and Hong Kong as well. British Prime Minister Boris Johnson responded to a Supreme Court rebuke by doubling down on his plans for a no-deal Brexit, while protesters in the Asian financial hub adopted ever-more militaristic tactics. Dig deeper into these and other topics you might have overlooked this week and click here for Bloomberg’s most compelling political photos from the past seven days.  Change in the Saudi Birthplace of Islam Is Eyed Warily WorldwideAs the birthplace of Islam, Saudi Arabia is the country that the world’s 1.8 million Muslims look to above all others. But, as Anisah Shukry, Arys Aditya and Archana Chaudhary​​​​​​​ write, the latest in a series of liberalizing reforms attributed to the modernizing influence of Crown Prince Mohammed Bin Salman runs counter to its reputation for religious conservatism.Sanders, Warren Compete for Who Can Tax Billionaires the MostSenator Elizabeth Warren’s wealth tax proposal is big. Senator Bernie Sanders’ is about 60% bigger. Laura Davison and Emma Kinery take a closer look at the jockeying between the two top progressive 2020 Democratic presidential candidates. Nigeria Runs on Generators and Nine Hours of Power a DayIn Africa’s most populous country, almost everyone depends on generators, including President Muhammadu Buhari. Anthony Osae-Brown and Ruth Olurounbi explore one of the biggest issues Buhari faces as he tries to reform a $400 billion economy that is too dependent on oil exports, has too many inefficient state-owned enterprises and is still struggling to recover from a slump in 2016.Hong Kong’s ‘Frontliners’ Say They’re Ready to Die for Movement Weeks of clashes have created determined teams of protesters whose tactics are shifting as clashes become militarized. Aaron Mc Nicholas spoke to some of them, including Fung, a 24-year-old doctor who seems an unlikely candidate to stand on the front line of Hong Kong’s most violent civil unrest in half a century. Mongolia’s Populist President Is the Trump of the SteppeBattulga Khaltmaa is a wealthy businessman riding a wave of discontent to the land’s highest office and cozying up to Russian President Vladimir Putin. Sound familiar? Matthew Campbell and Terrence Edwards profile Mongolia’s president. Orban and Europe’s Other Anti-Immigrant Leaders Have a SecretWhile Prime Minister Viktor Orban is leading an anti-immigrant vanguard in the European Union to protect it from people he calls “invaders,” Hungary and other nearby countries are quietly opening a door to foreigners, Zoltan Simon, Jasmina Kuzmanovic and Marek Strzelecki report. The Cold Calculus Behind Putin’s Lukewarm Embrace of Paris PactAfter nearly four years of foot-dragging, Russia President Vladimir Putin has finally decided to ratify the 2015 Paris Agreement – and the reasons have less to do with the fate of the planet than with geopolitics and gross domestic product, Natasha Doff, Ilya Arkhipov and Yuliya Fedorinova report. Dodging Death, Candidates Vie to Lead a Broken Afghan NationWith Afghanistan set to elect a new president in defiance of threats from a resurgent Taliban, candidate Sayed Noorullah Jalili speaks to Eltaf Najafizada about how high the stakes are for the war-torn nation. Italy’s Oil Giant Can No Longer Ignore the Civil War Next DoorItalian giant Eni has dominated Libya’s energy industry for six decades. But as Chiara Albanese and Caroline Alexander explain, the company’s future there hangs in the balance of a brewing civil war.And finally…Wondering what life will be like in the U.K. should Britain crash out of Europe a month from now without a divorce agreement? Read Joe Mayes and Alex Morales’s detailed account of what the first 24 hours after a no-deal Brexit might look like based on interviews, government documents, and academic research. To contact the author of this story: Kathleen Hunter in London at khunter9@bloomberg.netTo contact the editor responsible for this story: Karl Maier at kmaier2@bloomberg.netFor more articles like this, please visit us at bloomberg.com©2019 Bloomberg L.P.