本周早些时候，记者问我，为什么我在马德里参加联合国气候峰会，而不是回国参加竞选。答案很简单:我去是因为唐纳德·特朗普总统拒绝去。

总统拒绝领导气候变化，所以我们其他人必须这样做。他拒绝支持巴黎气候协议——尽管绝大多数美国人都支持。他拒绝支付美国的账单来资助气候峰会，所以我的基金会照做了——就像我们前两年做的那样。

周五，我很高兴站在弗吉尼亚州亚历山大市与来自全国各地的气候积极分子团结一致，这是我们成功的国家工作开始的地方。2011年，我们来到亚历山大，站在一座臭名昭著、肮脏的燃煤发电厂前。我们宣布发起一场运动，关闭那座肮脏的工厂——我们在一年后完成了这项工作——以及美国其他工厂。我们称我们的运动为超越煤炭。近十年后，它被称为现代环境运动中最成功的运动。

当我们启动时，我们的目标是到2020年淘汰三分之一的美国煤电厂。到目前为止，我们已经退休了一半以上——530人中的299人。现在我们已经设定了在2030年前让他们全部退休的目标。

特朗普没有停止美国的气候运动，尽管他尽了最大努力。在他说他将把美国从巴黎气候协议中撤出后，我和前加州州长杰里·布朗组成了一个名为“美国誓言”的小组。我们已经动员了大约4000个美国城市、州和企业致力于履行美国在巴黎气候协议下做出的承诺。

即使特朗普政府反对我们，我们也取得了很大成就。但是想象一下，有一位总统带路，我们还能做多少事情。

我正在竞选总统，以击败特朗普，他在椭圆形办公室的鲁莽和不道德行为威胁到我们的价值观和国家安全，并开始统一和重建美国，包括建立100%清洁能源经济。

在亚历山大，我为我们的国家设定了雄心勃勃的新气候目标，包括我们在未来八年内实际能够实现的目标。首先:我将争取到2028年将电力排放量减少80%，此后不久将实现100%的清洁电力。为了做到这一点，我们将用清洁能源取代美国所有的煤电厂。我们将更换现有的天然气厂，并停止建设新的天然气厂。(这一点至关重要，因为天然气现在是比煤炭更大的气候污染源，而且天然气的排放量正在增加。)我们将暂停联邦土地上所有新的化石燃料租赁。我们将结束对化石燃料公司超过100亿美元的补贴——不再有税收漏洞、税收减免或异乎寻常的减税。

作为总统，我将在2050年前加快美国向零碳经济的过渡。其他候选人谈论的是2045年或2050年——当他们长期离职的时候。我专注于立即取得进展。到2030年，我们将把整个美国经济的温室气体排放量减少50%。与此同时，我们将投资于能在2050年前尽可能快地将我们推向100%清洁能源经济的技术，因为我们的气候危机日益恶化。

我们不知道未来会出现什么样的技术进步，但我们可以加速它们的发展。为此，我将把我们在研发方面的年度投资翻两番，跨越多个联邦机构，并与私营部门合作，为清洁能源投资释放更多私人资本。

现在，特朗普危险地回滚保护清洁空气和饮用水的规则，让数百万美国人面临污染。风险最大的人是城市和农村地区的低收入美国人。我将扭转这些倒退，联邦机构将制定积极的健康和安全标准。

美国的城市和农村社区都受到化石燃料经济产生的有毒空气和有毒水的影响。很长一段时间以来，华盛顿都在朝另一个方向看。作为总统，我将把所有受灾最严重的社区放在我们优先考虑的名单的首位，包括那些为我们几代人提供煤炭的社区，他们自己和他们的家庭都面临巨大的风险和巨大的代价。

周五在弗吉尼亚展出的美国气候运动继续向前推进，但成功取决于提名一名能够击败一直试图拖我们后腿的总统的候选人。

MICHAEL BLOOMBERG: TRUMP REFUSES TO LEAD ON CLIMATE CHANGE—BUT I REFUSE TO WAIT | OPINION

Earlier this week, reporters asked me why I was in Madrid for the U.N. climate summit rather than back home on the campaign trail. The answer was simple: I went because President Donald Trump refused to go.

The president refuses to lead on climate change, so the rest of us must. He has refused to support the Paris Climate Agreement—even though Americans overwhelmingly do. He refused to pay America's bill to help fund the climate summit, so my foundation did—just as we did the previous two years.

On Friday, I was glad to stand in solidarity with climate activists from across the country in Alexandria, Virginia—the place where our successful national work got its start. In 2011, we came to Alexandria and stood in front of a notorious, dirty, coal-fired power plant. We announced a campaign to close down that dirty plant—we got it done a year later—and other plants across America. We called our campaign Beyond Coal. Nearly a decade later, it has been called the most successful campaign of the modern environmental movement.

When we launched, our goal was to retire one-third of U.S. coal plants by 2020. So far, we've retired more than half—299 out of 530. And now we've set a goal of retiring all of them by 2030.

Trump has not stopped America's climate movement, despite his best efforts. After he said he would pull the U.S. out of the Paris Climate Agreement, I formed a group with former California Governor Jerry Brown called America's Pledge. We've galvanized some 4,000 U.S. cities, states and businesses that are devoted to meeting the commitment the U.S. made under the Paris Climate Agreement.

We've accomplished a lot even with the Trump administration working against us. But imagine how much more we can do with a president who leads the way.

I'm running for president to defeat Trump, whose reckless and unethical behavior in the Oval Office is a threat to our values and national security, and start reuniting and rebuilding America, including by building a 100 percent clean energy economy.

In Alexandria, I set ambitious new climate goals for our country, including goals that we can actually achieve over the next eight years. First: I will push for an 80 percent reduction in electricity emissions by 2028 and 100 percent clean electricity shortly thereafter. To get it done, we'll replace all U.S. coal plants with clean energy. We'll replace existing gas plants, and we'll stop the construction of new gas plants. (This is critical, because gas is now a bigger source of climate pollution than coal, and emissions from gas are growing.) We'll put a moratorium on all new fossil-fuel leases on federal lands. And we'll end the over $10 billion in subsidies for fossil fuel companies—no more tax loopholes, tax breaks or egregious tax deductions.

As president, I'll accelerate America's transition to a zero-carbon economy before 2050. Other candidates talk about 2045 or 2050—when they're long out of office. I'm focused on delivering progress immediately. We will cut greenhouse emissions across the entire U.S. economy by 50 percent by 2030. At the same time, we will invest in technology that can move us as fast as humanly possible to a 100 percent clean energy economy, before 2050, because we have a climate crisis growing worse by the day.

Former New York Mayor and Democratic presidential candidate Michael Bloomberg arrives to speak about his plan for clean energy during a campaign event at the Blackwall Hitch restaurant in Alexandria, Virginia, on December 13.

We don't know what technological advancements will occur in the future, but we can accelerate their development. To do that, I'll quadruple our annual investment in research and development, across multiple federal agencies, and work with the private sector to unlock more private capital for clean energy investment.

Right now, Trump's dangerous rollbacks of rules that protect clean air and drinking water are exposing millions of Americans to pollution. The people who are most at-risk are low-income Americans in both urban and rural areas. I'll reverse those rollbacks, and federal agencies will set aggressive health and safety standards.

Communities across America—both urban and rural—have suffered from the toxic air and poisoned water that the fossil-fuel economy produced. For far too long, Washington looked the other way. As president, I will put all of the hardest-hit communities at the top of our priority list, including all those that provided us with coal for generations, at great risk and enormous cost to themselves and their families.

The American climate movement that was on display in Virginia on Friday keeps forging ahead, but success depends on nominating a candidate who can defeat a president who keeps trying to drag us backwards.

Michael Bloomberg is a Democratic candidate for president of the United States.