Trump vows allies won't 'take advantage' after Mattis exit

President Donald Trump vowed Monday that allies would no longer "take advantage" of the United States, taking a shot at Defense Secretary Jim Mattis who resigned over Syria. Trump, turning to Twitter after days of criticism over his decision to pull US troops out of Syria, denied charges that he was rejecting allies. But he said that "these same countries take advantage of their friendship with the United States." "We are substantially subsidizing the Militaries of many VERY rich countries all over the world, while at the same time these countries take total advantage of the U.S., and our TAXPAYERS, on Trade," he tweeted. "General Mattis did not see this as a problem. I DO, and it is being fixed!" Amid open concern about the Syria pullout from allies including France and Germany, Trump tweeted in all capital letters: "AMERICA IS RESPECTED AGAIN!" Mattis, a battle-hardened retired four-star general widely seen as a moderating force on the impulsive president, in his resignation letter Thursday emphasized the need to respect allies. Trump has repeatedly berated close US friends and questioned the cost-effectiveness of NATO, the North American and European military alliance established seven decades ago as a bulwark against Moscow. Mattis took his criticism public after Trump suddenly announced the pullout of all 2,000 troops from Syria, saying that the Islamic State extremist group, also known as ISIS, had been defeated. Trump said he coordinated with Turkish President Recep Tayyip Erdogan -- who has been warning that he will attack US-allied Kurdish fighters who had seized ground from ISIS. Senator Lindsey Graham, a usual ally of Trump who has been harshly critical of the Syria decision, on Monday tried a different strategy as he appealed to the president to work off his diplomacy with Erdogan. Graham said that the United States could reduce, but not completely pull out, troops from Syria and "partner" with Turkey. "'Partnering' with Turkey to destroy ISIS -- and ensuring protection for the Kurds who fought so bravely -- is a big win," he tweeted.