Friend,
You may think Satan has the upper-hand advantage right now because of what you see around the world is contamination. However, you have to understand that Satan is only a mere character in God's plan. In other words, God is in control of everything and therefore, no matter which direction Satan takes -- he will meet his eventual demise as written in Revelation. You have to know that even if humans are blinded by the darkness and by Satan's influence, in the end, he has nowhere to run. Satan was defeated when Jesus died on the cross. He can not overpower God for he's not in control of the plan, God is.
"For we know that since Christ was raised from the dead, he cannot die again; death no longer has mastery over him." - Romans 6:9
"Do not take revenge, my friends, but leave room for God's wrath, for it is written: “It is mine to avenge; I will repay,”says the Lord." - Romans 12:19
"That is why, for Christ's sake, I delight in weaknesses, in insults, in hardships, in persecutions, in difficulties. For when I am weak, then I am strong." - 2 Corinthians 10:12
"I tell you, my friends, do not be afraid of those who kill the body and after that can do no more. But I will show you whom you should fear: Fear him who, after the killing of the body, has power to throw you into hell. Yes, I tell you, fear him." - Luke 12:4-5
"I eagerly expect and hope that I will in no way be ashamed, but will have sufficient courage so that now as always Christ will be exalted in my body, whether by life or by death." - Phillipians 1:20
However, of course just because we're saved and under God's grace...does that mean we can underestimate Satan? Certainly not! The reason is because when we put our guards down, that's when we're prone to being tempted and led astray.
"You too should be on your guard against him, because he strongly opposed our message." - 2 Timothy 4:15
"Therefore, dear friends, since you already know this, be on your guard so that you may not be carried away by the error of lawless men and fall from your secure position." - 2 Peter 3:17
"Finally, be strong in the Lord and in his mighty power. Put on the full armor of God so that you can take your stand against the devil's schemes. For our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this dark world and against the spiritual forces of evil in the heavenly realms. Therefore put on the full armor of God, so that when the day of evil comes, you may be able to stand your ground, and after you have done everything, to stand. Stand firm then, with the belt of truth buckled around your waist, with the breastplate of righteousness in place, and with your feet fitted with the readiness that comes from the gospel of peace. In addition to all this, take up the shield of faith, with which you can extinguish all the flaming arrows of the evil one. Take the helmet of salvation and the sword of the Spirit, which is the word of God. And pray in the Spirit on all occasions with all kinds of prayers and requests. With this in mind, be alert and always keep on praying for all the saints." - Ephesians 6:10-18
You must also understand that Love is much greater than Hate. By the Gospel, it corrects, rebukes and encourages but also shuts the mouths of those who oppose because they know that their errors have been corrected. The Devil is the Father of Deception and will only use half-truths to accuse you. However, the full truth and the full power of God -- this he cannot scratch.